From 160ebd649d4641138c1ffd2bdded43ddb7807a3d Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Sat, 28 Aug 2021 23:27:35 +0200
Subject: [PATCH 01/37] Most coercions implemented

---
 ablescript/src/ast.rs       |   2 +-
 ablescript/src/interpret.rs |  96 ++++-------
 ablescript/src/parser.rs    |   5 +-
 ablescript/src/variables.rs | 322 +++++++++++++++++++++++++++++-------
 4 files changed, 298 insertions(+), 127 deletions(-)

diff --git a/ablescript/src/ast.rs b/ablescript/src/ast.rs
index 9043283..0d68f11 100644
--- a/ablescript/src/ast.rs
+++ b/ablescript/src/ast.rs
@@ -142,7 +142,7 @@ pub enum ExprKind {
     Literal(Value),
     Cart(Vec<(Expr, Expr)>),
     Index {
-        cart: Box<Expr>,
+        expr: Box<Expr>,
         index: Box<Expr>,
     },
     Variable(String),
diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index 1f0f0f6..73e9ed8 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -141,59 +141,19 @@ impl ExecEnv {
                 let lhs = self.eval_expr(lhs)?;
                 let rhs = self.eval_expr(rhs)?;
                 match kind {
-                    // Arithmetic operators.
-                    Add | Subtract | Multiply | Divide => {
-                        let lhs = lhs.to_i32();
-                        let rhs = rhs.to_i32();
-
-                        let res = match kind {
-                            Add => lhs.checked_add(rhs),
-                            Subtract => lhs.checked_sub(rhs),
-                            Multiply => lhs.checked_mul(rhs),
-                            Divide => lhs.checked_div(rhs),
-                            _ => unreachable!(),
-                        }
-                        .unwrap_or(consts::ANSWER);
-                        Int(res)
-                    }
-
-                    // Numeric comparisons.
-                    Less | Greater => {
-                        let lhs = lhs.to_i32();
-                        let rhs = rhs.to_i32();
-
-                        let res = match kind {
-                            Less => lhs < rhs,
-                            Greater => lhs > rhs,
-                            _ => unreachable!(),
-                        };
-                        Bool(res)
-                    }
-
-                    // General comparisons.
-                    Equal | NotEqual => {
-                        let res = match kind {
-                            Equal => lhs == rhs,
-                            NotEqual => lhs != rhs,
-                            _ => unreachable!(),
-                        };
-                        Bool(res)
-                    }
-
-                    // Logical connectives.
-                    And | Or => {
-                        let lhs = lhs.to_bool();
-                        let rhs = rhs.to_bool();
-                        let res = match kind {
-                            And => lhs && rhs,
-                            Or => lhs || rhs,
-                            _ => unreachable!(),
-                        };
-                        Bool(res)
-                    }
+                    Add => lhs + rhs,
+                    Subtract => todo!(),
+                    Multiply => todo!(),
+                    Divide => todo!(),
+                    Greater => Value::Bool(lhs > rhs),
+                    Less => Value::Bool(lhs < rhs),
+                    Equal => Value::Bool(lhs == rhs),
+                    NotEqual => Value::Bool(lhs != rhs),
+                    And => todo!(),
+                    Or => todo!(),
                 }
             }
-            Not(expr) => Bool(!self.eval_expr(expr)?.to_bool()),
+            Not(expr) => Bool(!self.eval_expr(expr)?.into_bool()),
             Literal(value) => value.clone(),
             ExprKind::Cart(members) => Value::Cart(
                 members
@@ -206,12 +166,15 @@ impl ExecEnv {
                     })
                     .collect::<Result<HashMap<_, _>, _>>()?,
             ),
-            Index { cart, index } => {
-                let cart = self.eval_expr(cart)?;
+            Index { expr, index } => {
+                let value = self.eval_expr(expr)?;
                 let index = self.eval_expr(index)?;
 
-                // TODO: this probably shouldn't be cloned
-                cart.index(&index).borrow().clone()
+                value
+                    .into_cart()
+                    .get(&index)
+                    .map(|x| x.borrow().clone())
+                    .unwrap_or(Value::Nul)
             }
 
             // TODO: not too happy with constructing an artificial
@@ -257,24 +220,20 @@ impl ExecEnv {
                         instructions: code.to_owned(),
                         tape_len: tape_len
                             .as_ref()
-                            .map(|tape_len| self.eval_expr(tape_len).map(|v| v.to_i32() as usize))
+                            .map(|tape_len| self.eval_expr(tape_len).map(|v| v.into_i32() as usize))
                             .unwrap_or(Ok(crate::brian::DEFAULT_TAPE_SIZE_LIMIT))?,
                     }),
                 );
             }
             StmtKind::If { cond, body } => {
-                if self.eval_expr(cond)?.to_bool() {
+                if self.eval_expr(cond)?.into_bool() {
                     return self.eval_stmts_hs(&body.block, true);
                 }
             }
             StmtKind::Call { expr, args } => {
-                let func = self.eval_expr(expr)?;
+                let func = self.eval_expr(expr)?.into_functio();
 
-                if let Value::Functio(func) = func {
-                    self.fn_call(func, args, &stmt.span)?;
-                } else {
-                    // Fail silently for now.
-                }
+                self.fn_call(func, args, &stmt.span)?;
             }
             StmtKind::Loop { body } => loop {
                 let res = self.eval_stmts_hs(&body.block, true)?;
@@ -387,6 +346,17 @@ impl ExecEnv {
                 self.stack.pop();
                 res?;
             }
+            Functio::Eval(code) => {
+                if args.len() != 0 {
+                    return Err(Error {
+                        kind: ErrorKind::MismatchedArgumentError,
+                        span: span.to_owned(),
+                    });
+                }
+
+                let stmts = crate::parser::Parser::new(&code).init()?;
+                self.eval_stmts(&stmts)?;
+            }
         }
         Ok(())
     }
diff --git a/ablescript/src/parser.rs b/ablescript/src/parser.rs
index f42873e..16c6733 100644
--- a/ablescript/src/parser.rs
+++ b/ablescript/src/parser.rs
@@ -98,6 +98,7 @@ impl<'source> Parser<'source> {
             | Token::Integer(_)
             | Token::Abool(_)
             | Token::Bool(_)
+            | Token::Nul
             | Token::LeftBracket
             | Token::LeftParen => Ok(Stmt::new(
                 self.value_flow(token)?,
@@ -192,7 +193,7 @@ impl<'source> Parser<'source> {
             Token::LeftBracket => match buf.take() {
                 Some(buf) => Ok(Expr::new(
                     ExprKind::Index {
-                        cart: Box::new(buf),
+                        expr: Box::new(buf),
                         index: Box::new(self.expr_flow(Token::RightBracket)?),
                     },
                     start..self.lexer.span().end,
@@ -728,7 +729,7 @@ mod tests {
         let expected = &[Stmt {
             kind: StmtKind::Print(Expr {
                 kind: ExprKind::Index {
-                    cart: Box::new(Expr {
+                    expr: Box::new(Expr {
                         kind: ExprKind::Cart(vec![(
                             Expr {
                                 kind: ExprKind::Literal(Value::Str("able".to_string())),
diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index f088b16..57a9c7c 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -1,6 +1,6 @@
 use std::{
     cell::RefCell, collections::HashMap, convert::TryFrom, fmt::Display, hash::Hash, io::Write,
-    mem::discriminant, rc::Rc,
+    mem::discriminant, ops, rc::Rc, vec,
 };
 
 use rand::Rng;
@@ -44,8 +44,11 @@ pub enum Functio {
         params: Vec<String>,
         body: Vec<Stmt>,
     },
+    Eval(String),
 }
 
+pub type Cart = HashMap<Value, Rc<RefCell<Value>>>;
+
 #[derive(Debug, Clone)]
 pub enum Value {
     Nul,
@@ -54,7 +57,7 @@ pub enum Value {
     Bool(bool),
     Abool(Abool),
     Functio(Functio),
-    Cart(HashMap<Value, Rc<RefCell<Value>>>),
+    Cart(Cart),
 }
 
 impl Hash for Value {
@@ -72,24 +75,6 @@ impl Hash for Value {
     }
 }
 
-impl PartialEq for Value {
-    fn eq(&self, other: &Self) -> bool {
-        match (self, other) {
-            (Value::Nul, Value::Nul) => true,
-            (Value::Str(left), Value::Str(right)) => left == right,
-            (Value::Int(left), Value::Int(right)) => left == right,
-            (Value::Bool(left), Value::Bool(right)) => left == right,
-            (Value::Abool(left), Value::Abool(right)) => left == right,
-            (Value::Functio(left), Value::Functio(right)) => left == right,
-            (Value::Cart(_), Value::Cart(_)) => self.to_string() == other.to_string(),
-            (_, _) => false,
-            // TODO: do more coercions!
-        }
-    }
-}
-
-impl Eq for Value {}
-
 impl Value {
     /// Write an AbleScript value to a Brainfuck input stream by
     /// coercing the value to an integer, then truncating that integer
@@ -98,23 +83,24 @@ impl Value {
     /// any IO errors will cause a panic.
     pub fn bf_write(&self, stream: &mut impl Write) {
         stream
-            .write_all(&[self.clone().to_i32() as u8])
+            .write_all(&[self.clone().into_i32() as u8])
             .expect("Failed to write to Brainfuck input");
     }
 
     /// Coerce a value to an integer.
-    pub fn to_i32(&self) -> i32 {
+    pub fn into_i32(self) -> i32 {
         match self {
-            Value::Abool(a) => *a as _,
-            Value::Bool(b) => *b as _,
+            Value::Abool(a) => a as _,
+            Value::Bool(b) => b as _,
             Value::Functio(func) => match func {
                 Functio::BfFunctio {
                     instructions,
                     tape_len,
                 } => (instructions.len() + tape_len) as _,
                 Functio::AbleFunctio { params, body } => (params.len() + body.len()) as _,
+                Functio::Eval(s) => s.parse().unwrap_or(consts::ANSWER),
             },
-            Value::Int(i) => *i,
+            Value::Int(i) => i,
             Value::Nul => consts::ANSWER,
             Value::Str(text) => text.parse().unwrap_or(consts::ANSWER),
             Value::Cart(c) => c.len() as _,
@@ -122,49 +108,262 @@ impl Value {
     }
 
     /// Coerce a Value to a boolean. The conversion cannot fail.
-    pub fn to_bool(&self) -> bool {
+    pub fn into_bool(self) -> bool {
         match self {
-            Value::Abool(b) => (*b).into(),
-            Value::Bool(b) => *b,
+            Value::Abool(b) => b.into(),
+            Value::Bool(b) => b,
             Value::Functio(_) => true,
-            Value::Int(x) => *x != 0,
-            Value::Nul => true,
-            Value::Str(s) => !s.is_empty(),
+            Value::Int(x) => x != 0,
+            Value::Nul => false,
+            Value::Str(s) => match s.to_lowercase().as_str() {
+                "false" | "no" | "🇳🇴" => false,
+                "true" | "yes" => true,
+                s => !s.is_empty(),
+            },
             Value::Cart(c) => !c.is_empty(),
         }
     }
 
-    /// Index a value with another value, as in the "a[b]" syntax.
-    pub fn index(&self, index: &Value) -> Rc<RefCell<Value>> {
-        Rc::new(RefCell::new(match self {
-            Value::Nul => Value::Nul,
-            Value::Str(s) => Value::Int(
-                usize::try_from(index.to_i32() - 1)
-                    .ok()
-                    .and_then(|idx| s.as_bytes().get(idx).cloned())
-                    .map(|value| value as i32)
-                    .unwrap_or(0),
-            ),
-            Value::Int(i) => Value::Int(
-                usize::try_from(index.to_i32() - 1)
-                    .ok()
-                    .and_then(|idx| format!("{}", i).as_bytes().get(idx).cloned())
-                    .map(|value| value as i32)
-                    .unwrap_or(0),
-            ),
-            Value::Bool(b) => Value::Int(
-                usize::try_from(index.to_i32() - 1)
-                    .ok()
-                    .and_then(|idx| format!("{}", b).as_bytes().get(idx).cloned())
-                    .map(|value| value as i32)
-                    .unwrap_or(0),
-            ),
-            Value::Abool(b) => Value::Int(*b as i32),
-            Value::Functio(_) => Value::Int(42),
-            Value::Cart(c) => {
-                return (c.get(index).cloned()).unwrap_or_else(|| Rc::new(RefCell::new(Value::Nul)))
+    /// Coerce a Value to an aboolean
+    pub fn into_abool(self) -> Abool {
+        match self {
+            Value::Nul => Abool::Never,
+            Value::Str(s) => match s.to_lowercase().as_str() {
+                "never" => Abool::Never,
+                "sometimes" => Abool::Sometimes,
+                "always" => Abool::Always,
+                s => {
+                    if s.is_empty() {
+                        Abool::Never
+                    } else {
+                        Abool::Always
+                    }
+                }
+            },
+            Value::Int(x) => match x.cmp(&0) {
+                std::cmp::Ordering::Less => Abool::Never,
+                std::cmp::Ordering::Equal => Abool::Sometimes,
+                std::cmp::Ordering::Greater => Abool::Always,
+            },
+            Value::Bool(b) => {
+                if b {
+                    Abool::Always
+                } else {
+                    Abool::Never
+                }
             }
-        }))
+            Value::Abool(a) => a,
+            Value::Functio(_) => todo!(),
+            Value::Cart(c) => {
+                if c.is_empty() {
+                    Abool::Never
+                } else {
+                    Abool::Always
+                }
+            }
+        }
+    }
+
+    /// Coerce a Value to a functio
+    pub fn into_functio(self) -> Functio {
+        match self {
+            Value::Nul => Functio::AbleFunctio {
+                body: vec![],
+                params: vec![],
+            },
+            Value::Str(s) => Functio::Eval(s),
+            Value::Int(i) => todo!(),
+            Value::Bool(_) => todo!(),
+            Value::Abool(_) => todo!(),
+            Value::Functio(f) => f,
+            Value::Cart(_) => todo!(),
+        }
+    }
+
+    pub fn into_cart(self) -> Cart {
+        match self {
+            Value::Nul => HashMap::new(),
+            Value::Str(s) => s
+                .chars()
+                .enumerate()
+                .map(|(i, x)| {
+                    (
+                        Value::Int(i as i32 + 1),
+                        Rc::new(RefCell::new(Value::Str(x.to_string()))),
+                    )
+                })
+                .collect(),
+            Value::Int(i) => Value::Str(i.to_string()).into_cart(),
+            Value::Bool(b) => Value::Str(b.to_string()).into_cart(),
+            Value::Abool(a) => Value::Str(a.to_string()).into_cart(),
+            Value::Functio(f) => match f {
+                Functio::BfFunctio {
+                    instructions,
+                    tape_len,
+                } => {
+                    let mut cart: Cart = instructions
+                        .into_iter()
+                        .enumerate()
+                        .map(|(i, x)| {
+                            (
+                                Value::Int(i as i32 + 1),
+                                Rc::new(RefCell::new(
+                                    char::from_u32(x as u32)
+                                        .map(|x| Value::Str(x.to_string()))
+                                        .unwrap_or(Value::Nul),
+                                )),
+                            )
+                        })
+                        .collect();
+
+                    cart.insert(
+                        Value::Str("tapelen".to_owned()),
+                        Rc::new(RefCell::new(Value::Int(tape_len as _))),
+                    );
+                    cart
+                }
+                Functio::AbleFunctio { params, body } => {
+                    let params: Cart = params
+                        .into_iter()
+                        .enumerate()
+                        .map(|(i, x)| {
+                            (
+                                Value::Int(i as i32 + 1),
+                                Rc::new(RefCell::new(Value::Str(x))),
+                            )
+                        })
+                        .collect();
+
+                    let body: Cart = body
+                        .into_iter()
+                        .enumerate()
+                        .map(|(i, x)| {
+                            (
+                                Value::Int(i as i32 + 1),
+                                Rc::new(RefCell::new(Value::Str(format!("{:?}", x)))),
+                            )
+                        })
+                        .collect();
+
+                    let mut cart = HashMap::new();
+                    cart.insert(
+                        Value::Str("params".to_owned()),
+                        Rc::new(RefCell::new(Value::Cart(params))),
+                    );
+
+                    cart.insert(
+                        Value::Str("body".to_owned()),
+                        Rc::new(RefCell::new(Value::Cart(body))),
+                    );
+
+                    cart
+                }
+                Functio::Eval(s) => Value::Str(s).into_cart(),
+            },
+            Value::Cart(c) => c,
+        }
+    }
+}
+
+impl ops::Add for Value {
+    type Output = Value;
+
+    fn add(self, rhs: Self) -> Self::Output {
+        match self {
+            Value::Nul => todo!(),
+            Value::Str(s) => Value::Str(format!("{}{}", s, rhs.to_string())),
+            Value::Int(i) => Value::Int(i + rhs.into_i32()),
+            Value::Bool(b) => Value::Bool(b ^ rhs.into_bool()),
+            Value::Abool(a) => Value::Abool({
+                let rhs = rhs.into_abool();
+                if a == rhs {
+                    a
+                } else if a == Abool::Sometimes {
+                    if rand::thread_rng().gen() {
+                        Abool::Sometimes
+                    } else {
+                        rhs
+                    }
+                } else if rhs == Abool::Sometimes {
+                    if rand::thread_rng().gen() {
+                        Abool::Sometimes
+                    } else {
+                        a
+                    }
+                } else {
+                    Abool::Sometimes
+                }
+            }),
+            Value::Functio(f) => Value::Functio(todo!()),
+            Value::Cart(c) => {
+                Value::Cart(c.into_iter().chain(rhs.into_cart().into_iter()).collect())
+            }
+        }
+    }
+}
+
+impl ops::Sub for Value {
+    type Output = Value;
+
+    fn sub(self, rhs: Self) -> Self::Output {
+        todo!()
+    }
+}
+
+impl ops::Mul for Value {
+    type Output = Value;
+
+    fn mul(self, rhs: Self) -> Self::Output {
+        todo!()
+    }
+}
+
+impl ops::Div for Value {
+    type Output = Value;
+
+    fn div(self, rhs: Self) -> Self::Output {
+        todo!()
+    }
+}
+
+impl PartialEq for Value {
+    fn eq(&self, other: &Self) -> bool {
+        let other = other.clone();
+
+        match self {
+            Value::Nul => other == Value::Nul,
+            Value::Str(s) => *s == other.to_string(),
+            Value::Int(i) => *i == other.into_i32(),
+            Value::Bool(b) => *b == other.into_bool(),
+            Value::Abool(a) => *a == other.into_abool(),
+            Value::Functio(f) => *f == other.into_functio(),
+            Value::Cart(c) => *c == other.into_cart(),
+        }
+    }
+}
+
+impl Eq for Value {}
+
+impl PartialOrd for Value {
+    fn partial_cmp(&self, other: &Self) -> Option<std::cmp::Ordering> {
+        use std::cmp::Ordering::*;
+        let other = other.clone();
+
+        match self {
+            Value::Nul => {
+                if other == Value::Nul {
+                    Some(Equal)
+                } else {
+                    None
+                }
+            }
+            Value::Str(_) => todo!(),
+            Value::Int(_) => todo!(),
+            Value::Bool(_) => todo!(),
+            Value::Abool(_) => todo!(),
+            Value::Functio(_) => todo!(),
+            Value::Cart(_) => todo!(),
+        }
     }
 }
 
@@ -199,6 +398,7 @@ impl Display for Value {
                         body,
                     )
                 }
+                Functio::Eval(s) => write!(f, "{}", s),
             },
             Value::Cart(c) => {
                 write!(f, "[")?;

From 2010b131682155b536b7ec25199531399af9c2ec Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Sat, 28 Aug 2021 23:43:59 +0200
Subject: [PATCH 02/37] Implement custom `PartialEq` for `Value`

---
 ablescript/src/variables.rs | 39 ++++++++++++++++++++++++++++++-------
 1 file changed, 32 insertions(+), 7 deletions(-)

diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index 57a9c7c..3fa3fa0 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -7,7 +7,7 @@ use rand::Rng;
 
 use crate::{ast::Stmt, consts};
 
-#[derive(Debug, Clone, Copy, PartialEq)]
+#[derive(Debug, Clone, Copy, PartialEq, PartialOrd)]
 pub enum Abool {
     Never = -1,
     Sometimes = 0,
@@ -357,12 +357,37 @@ impl PartialOrd for Value {
                     None
                 }
             }
-            Value::Str(_) => todo!(),
-            Value::Int(_) => todo!(),
-            Value::Bool(_) => todo!(),
-            Value::Abool(_) => todo!(),
-            Value::Functio(_) => todo!(),
-            Value::Cart(_) => todo!(),
+            Value::Str(s) => Some(s.cmp(&other.to_string())),
+            Value::Int(i) => Some(i.cmp(&other.into_i32())),
+            Value::Bool(b) => Some(b.cmp(&other.into_bool())),
+            Value::Abool(a) => a.partial_cmp(&other.into_abool()),
+            Value::Functio(f) => {
+                // Compares lengths of functions:
+                // BfFunctio - Sum of lengths of instructions and length of tape
+                // AbleFunctio - Sum of argument count and body length
+                // Eval - Length of input code
+
+                let selfl = match f {
+                    Functio::BfFunctio {
+                        instructions,
+                        tape_len,
+                    } => instructions.len() + tape_len,
+                    Functio::AbleFunctio { params, body } => params.len() + body.len(),
+                    Functio::Eval(s) => s.len(),
+                };
+
+                let otherl = match other.into_functio() {
+                    Functio::BfFunctio {
+                        instructions,
+                        tape_len,
+                    } => instructions.len() + tape_len,
+                    Functio::AbleFunctio { params, body } => params.len() + body.len(),
+                    Functio::Eval(s) => s.len(),
+                };
+
+                Some(selfl.cmp(&otherl))
+            }
+            Value::Cart(c) => Some(c.len().cmp(&other.into_cart().len())),
         }
     }
 }

From 1b243d142c9047b845414580adf83fde45604b55 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Sat, 28 Aug 2021 23:52:58 +0200
Subject: [PATCH 03/37] Display carts sorted

---
 ablescript/src/variables.rs | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index 3fa3fa0..544f29f 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -427,9 +427,11 @@ impl Display for Value {
             },
             Value::Cart(c) => {
                 write!(f, "[")?;
+                let mut cart_vec = c.into_iter().collect::<Vec<_>>();
+                cart_vec.sort_by(|x, y| x.0.partial_cmp(&y.0).unwrap_or(std::cmp::Ordering::Less));
 
-                for (key, value) in c {
-                    write!(f, "{} <= {},", value.borrow(), key)?;
+                for (key, value) in cart_vec {
+                    write!(f, "{} <= {}, ", value.borrow(), key)?;
                 }
 
                 write!(f, "]")

From e95e0744c6f9504aa735b9c93857b3a8171bf711 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Sat, 28 Aug 2021 23:55:36 +0200
Subject: [PATCH 04/37] Fixed add overflows

---
 ablescript/src/variables.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index 544f29f..20f0031 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -272,7 +272,7 @@ impl ops::Add for Value {
         match self {
             Value::Nul => todo!(),
             Value::Str(s) => Value::Str(format!("{}{}", s, rhs.to_string())),
-            Value::Int(i) => Value::Int(i + rhs.into_i32()),
+            Value::Int(i) => Value::Int(i.checked_add(rhs.into_i32()).unwrap_or(consts::ANSWER)),
             Value::Bool(b) => Value::Bool(b ^ rhs.into_bool()),
             Value::Abool(a) => Value::Abool({
                 let rhs = rhs.into_abool();

From 24b6683b2100b71d352fc6be9006c138f1d12944 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Sat, 28 Aug 2021 23:59:04 +0200
Subject: [PATCH 05/37] Added placeholders for And + Or and used placeholders
 for -, * and / in interpret

---
 ablescript/src/interpret.rs | 10 +++++-----
 ablescript/src/variables.rs | 16 ++++++++++++++++
 2 files changed, 21 insertions(+), 5 deletions(-)

diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index 73e9ed8..656583a 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -142,15 +142,15 @@ impl ExecEnv {
                 let rhs = self.eval_expr(rhs)?;
                 match kind {
                     Add => lhs + rhs,
-                    Subtract => todo!(),
-                    Multiply => todo!(),
-                    Divide => todo!(),
+                    Subtract => lhs - rhs,
+                    Multiply => lhs * rhs,
+                    Divide => lhs / rhs,
                     Greater => Value::Bool(lhs > rhs),
                     Less => Value::Bool(lhs < rhs),
                     Equal => Value::Bool(lhs == rhs),
                     NotEqual => Value::Bool(lhs != rhs),
-                    And => todo!(),
-                    Or => todo!(),
+                    And => lhs & rhs,
+                    Or => lhs | rhs,
                 }
             }
             Not(expr) => Bool(!self.eval_expr(expr)?.into_bool()),
diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index 20f0031..7a5492a 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -392,6 +392,22 @@ impl PartialOrd for Value {
     }
 }
 
+impl ops::BitAnd for Value {
+    type Output = Value;
+
+    fn bitand(self, rhs: Self) -> Self::Output {
+        todo!()
+    }
+}
+
+impl ops::BitOr for Value {
+    type Output = Value;
+
+    fn bitor(self, rhs: Self) -> Self::Output {
+        todo!()
+    }
+}
+
 impl Display for Value {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {

From f08778ca3e8a8d3752d19e66bfc74b261475a73a Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Sun, 29 Aug 2021 00:07:26 +0200
Subject: [PATCH 06/37] Eval's integer representation is now its length -
 consistency with other types

---
 ablescript/src/variables.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index 7a5492a..3a5b186 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -98,7 +98,7 @@ impl Value {
                     tape_len,
                 } => (instructions.len() + tape_len) as _,
                 Functio::AbleFunctio { params, body } => (params.len() + body.len()) as _,
-                Functio::Eval(s) => s.parse().unwrap_or(consts::ANSWER),
+                Functio::Eval(s) => s.len() as _,
             },
             Value::Int(i) => i,
             Value::Nul => consts::ANSWER,

From c764cda7c7085f39423c343f330fbefb7147ddf0 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Sun, 29 Aug 2021 00:10:44 +0200
Subject: [PATCH 07/37] AbleFunctio's body length is now by it's string
 representation

---
 ablescript/src/variables.rs | 34 +++++++---------------------------
 1 file changed, 7 insertions(+), 27 deletions(-)

diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index 3a5b186..5d3eada 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -93,11 +93,16 @@ impl Value {
             Value::Abool(a) => a as _,
             Value::Bool(b) => b as _,
             Value::Functio(func) => match func {
+                // Compares lengths of functions:
+                // BfFunctio - Sum of lengths of instructions and length of tape
+                // AbleFunctio - Sum of argument count and body length
+                // Eval - Length of input code
+
                 Functio::BfFunctio {
                     instructions,
                     tape_len,
                 } => (instructions.len() + tape_len) as _,
-                Functio::AbleFunctio { params, body } => (params.len() + body.len()) as _,
+                Functio::AbleFunctio { params, body } => (params.len() + format!("{:?}", body).len()) as _,
                 Functio::Eval(s) => s.len() as _,
             },
             Value::Int(i) => i,
@@ -361,32 +366,7 @@ impl PartialOrd for Value {
             Value::Int(i) => Some(i.cmp(&other.into_i32())),
             Value::Bool(b) => Some(b.cmp(&other.into_bool())),
             Value::Abool(a) => a.partial_cmp(&other.into_abool()),
-            Value::Functio(f) => {
-                // Compares lengths of functions:
-                // BfFunctio - Sum of lengths of instructions and length of tape
-                // AbleFunctio - Sum of argument count and body length
-                // Eval - Length of input code
-
-                let selfl = match f {
-                    Functio::BfFunctio {
-                        instructions,
-                        tape_len,
-                    } => instructions.len() + tape_len,
-                    Functio::AbleFunctio { params, body } => params.len() + body.len(),
-                    Functio::Eval(s) => s.len(),
-                };
-
-                let otherl = match other.into_functio() {
-                    Functio::BfFunctio {
-                        instructions,
-                        tape_len,
-                    } => instructions.len() + tape_len,
-                    Functio::AbleFunctio { params, body } => params.len() + body.len(),
-                    Functio::Eval(s) => s.len(),
-                };
-
-                Some(selfl.cmp(&otherl))
-            }
+            Value::Functio(_) => self.clone().into_i32().partial_cmp(&other.into_i32()),
             Value::Cart(c) => Some(c.len().cmp(&other.into_cart().len())),
         }
     }

From 0cf8576a774d2774b5b87c2c26f3c83ff85bc240 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Sun, 29 Aug 2021 00:16:15 +0200
Subject: [PATCH 08/37] Eval errors are now correctly spanned

---
 ablescript/src/interpret.rs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index 656583a..cf85a10 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -355,7 +355,10 @@ impl ExecEnv {
                 }
 
                 let stmts = crate::parser::Parser::new(&code).init()?;
-                self.eval_stmts(&stmts)?;
+                self.eval_stmts(&stmts).map_err(|x| Error {
+                    span: span.clone(),
+                    ..x
+                })?;
             }
         }
         Ok(())

From 9b81ccf57ce84b0b2768fc017dd03163a9885a9c Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Sun, 29 Aug 2021 00:16:15 +0200
Subject: [PATCH 09/37] Eval errors are now correctly spanned

---
 ablescript/src/interpret.rs |  5 ++++-
 ablescript/src/variables.rs | 34 +++++++---------------------------
 2 files changed, 11 insertions(+), 28 deletions(-)

diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index 656583a..cf85a10 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -355,7 +355,10 @@ impl ExecEnv {
                 }
 
                 let stmts = crate::parser::Parser::new(&code).init()?;
-                self.eval_stmts(&stmts)?;
+                self.eval_stmts(&stmts).map_err(|x| Error {
+                    span: span.clone(),
+                    ..x
+                })?;
             }
         }
         Ok(())
diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index 3a5b186..5d3eada 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -93,11 +93,16 @@ impl Value {
             Value::Abool(a) => a as _,
             Value::Bool(b) => b as _,
             Value::Functio(func) => match func {
+                // Compares lengths of functions:
+                // BfFunctio - Sum of lengths of instructions and length of tape
+                // AbleFunctio - Sum of argument count and body length
+                // Eval - Length of input code
+
                 Functio::BfFunctio {
                     instructions,
                     tape_len,
                 } => (instructions.len() + tape_len) as _,
-                Functio::AbleFunctio { params, body } => (params.len() + body.len()) as _,
+                Functio::AbleFunctio { params, body } => (params.len() + format!("{:?}", body).len()) as _,
                 Functio::Eval(s) => s.len() as _,
             },
             Value::Int(i) => i,
@@ -361,32 +366,7 @@ impl PartialOrd for Value {
             Value::Int(i) => Some(i.cmp(&other.into_i32())),
             Value::Bool(b) => Some(b.cmp(&other.into_bool())),
             Value::Abool(a) => a.partial_cmp(&other.into_abool()),
-            Value::Functio(f) => {
-                // Compares lengths of functions:
-                // BfFunctio - Sum of lengths of instructions and length of tape
-                // AbleFunctio - Sum of argument count and body length
-                // Eval - Length of input code
-
-                let selfl = match f {
-                    Functio::BfFunctio {
-                        instructions,
-                        tape_len,
-                    } => instructions.len() + tape_len,
-                    Functio::AbleFunctio { params, body } => params.len() + body.len(),
-                    Functio::Eval(s) => s.len(),
-                };
-
-                let otherl = match other.into_functio() {
-                    Functio::BfFunctio {
-                        instructions,
-                        tape_len,
-                    } => instructions.len() + tape_len,
-                    Functio::AbleFunctio { params, body } => params.len() + body.len(),
-                    Functio::Eval(s) => s.len(),
-                };
-
-                Some(selfl.cmp(&otherl))
-            }
+            Value::Functio(_) => self.clone().into_i32().partial_cmp(&other.into_i32()),
             Value::Cart(c) => Some(c.len().cmp(&other.into_cart().len())),
         }
     }

From d6e99acdc9a295f514768dab1e4de18f353c6169 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Sun, 29 Aug 2021 00:26:40 +0200
Subject: [PATCH 10/37] Revert "Eval errors are now correctly spanned"

This reverts commit 9b81ccf57ce84b0b2768fc017dd03163a9885a9c.
---
 ablescript/src/interpret.rs |  5 +----
 ablescript/src/variables.rs | 34 +++++++++++++++++++++++++++-------
 2 files changed, 28 insertions(+), 11 deletions(-)

diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index cf85a10..656583a 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -355,10 +355,7 @@ impl ExecEnv {
                 }
 
                 let stmts = crate::parser::Parser::new(&code).init()?;
-                self.eval_stmts(&stmts).map_err(|x| Error {
-                    span: span.clone(),
-                    ..x
-                })?;
+                self.eval_stmts(&stmts)?;
             }
         }
         Ok(())
diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index 5d3eada..3a5b186 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -93,16 +93,11 @@ impl Value {
             Value::Abool(a) => a as _,
             Value::Bool(b) => b as _,
             Value::Functio(func) => match func {
-                // Compares lengths of functions:
-                // BfFunctio - Sum of lengths of instructions and length of tape
-                // AbleFunctio - Sum of argument count and body length
-                // Eval - Length of input code
-
                 Functio::BfFunctio {
                     instructions,
                     tape_len,
                 } => (instructions.len() + tape_len) as _,
-                Functio::AbleFunctio { params, body } => (params.len() + format!("{:?}", body).len()) as _,
+                Functio::AbleFunctio { params, body } => (params.len() + body.len()) as _,
                 Functio::Eval(s) => s.len() as _,
             },
             Value::Int(i) => i,
@@ -366,7 +361,32 @@ impl PartialOrd for Value {
             Value::Int(i) => Some(i.cmp(&other.into_i32())),
             Value::Bool(b) => Some(b.cmp(&other.into_bool())),
             Value::Abool(a) => a.partial_cmp(&other.into_abool()),
-            Value::Functio(_) => self.clone().into_i32().partial_cmp(&other.into_i32()),
+            Value::Functio(f) => {
+                // Compares lengths of functions:
+                // BfFunctio - Sum of lengths of instructions and length of tape
+                // AbleFunctio - Sum of argument count and body length
+                // Eval - Length of input code
+
+                let selfl = match f {
+                    Functio::BfFunctio {
+                        instructions,
+                        tape_len,
+                    } => instructions.len() + tape_len,
+                    Functio::AbleFunctio { params, body } => params.len() + body.len(),
+                    Functio::Eval(s) => s.len(),
+                };
+
+                let otherl = match other.into_functio() {
+                    Functio::BfFunctio {
+                        instructions,
+                        tape_len,
+                    } => instructions.len() + tape_len,
+                    Functio::AbleFunctio { params, body } => params.len() + body.len(),
+                    Functio::Eval(s) => s.len(),
+                };
+
+                Some(selfl.cmp(&otherl))
+            }
             Value::Cart(c) => Some(c.len().cmp(&other.into_cart().len())),
         }
     }

From e84c4b2a397824b508dccffb5380e67981f0e6d0 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Sun, 29 Aug 2021 00:28:45 +0200
Subject: [PATCH 11/37] Used body length for AbleFunctio to i32 instead of AST
 length

---
 ablescript/src/variables.rs | 29 ++---------------------------
 1 file changed, 2 insertions(+), 27 deletions(-)

diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index 3a5b186..a558ce3 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -97,7 +97,7 @@ impl Value {
                     instructions,
                     tape_len,
                 } => (instructions.len() + tape_len) as _,
-                Functio::AbleFunctio { params, body } => (params.len() + body.len()) as _,
+                Functio::AbleFunctio { params, body } => (params.len() + format!("{:?}", body).len()) as _,
                 Functio::Eval(s) => s.len() as _,
             },
             Value::Int(i) => i,
@@ -361,32 +361,7 @@ impl PartialOrd for Value {
             Value::Int(i) => Some(i.cmp(&other.into_i32())),
             Value::Bool(b) => Some(b.cmp(&other.into_bool())),
             Value::Abool(a) => a.partial_cmp(&other.into_abool()),
-            Value::Functio(f) => {
-                // Compares lengths of functions:
-                // BfFunctio - Sum of lengths of instructions and length of tape
-                // AbleFunctio - Sum of argument count and body length
-                // Eval - Length of input code
-
-                let selfl = match f {
-                    Functio::BfFunctio {
-                        instructions,
-                        tape_len,
-                    } => instructions.len() + tape_len,
-                    Functio::AbleFunctio { params, body } => params.len() + body.len(),
-                    Functio::Eval(s) => s.len(),
-                };
-
-                let otherl = match other.into_functio() {
-                    Functio::BfFunctio {
-                        instructions,
-                        tape_len,
-                    } => instructions.len() + tape_len,
-                    Functio::AbleFunctio { params, body } => params.len() + body.len(),
-                    Functio::Eval(s) => s.len(),
-                };
-
-                Some(selfl.cmp(&otherl))
-            }
+            Value::Functio(_) => self.clone().into_i32().partial_cmp(&other.into_i32()),
             Value::Cart(c) => Some(c.len().cmp(&other.into_cart().len())),
         }
     }

From e2c7a33a59d15f0951b31d358359e6abf557c9b4 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Sun, 29 Aug 2021 00:34:08 +0200
Subject: [PATCH 12/37] fmt + docs

---
 ablescript/src/variables.rs | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index a558ce3..dca8371 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -93,11 +93,17 @@ impl Value {
             Value::Abool(a) => a as _,
             Value::Bool(b) => b as _,
             Value::Functio(func) => match func {
+                // Compares lengths of functions:
+                // BfFunctio - Sum of lengths of instructions and length of tape
+                // AbleFunctio - Sum of argument count and body length
+                // Eval - Length of input code
                 Functio::BfFunctio {
                     instructions,
                     tape_len,
                 } => (instructions.len() + tape_len) as _,
-                Functio::AbleFunctio { params, body } => (params.len() + format!("{:?}", body).len()) as _,
+                Functio::AbleFunctio { params, body } => {
+                    (params.len() + format!("{:?}", body).len()) as _
+                }
                 Functio::Eval(s) => s.len() as _,
             },
             Value::Int(i) => i,

From 539989e2d02504fdd5957636b83bd13ca9c250bd Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Mon, 30 Aug 2021 22:14:13 +0200
Subject: [PATCH 13/37] Most of operations are implemented

---
 ablescript/src/variables.rs | 152 ++++++++++++++++++++++++++++--------
 1 file changed, 119 insertions(+), 33 deletions(-)

diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index dca8371..4e636a3 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -1,6 +1,14 @@
 use std::{
-    cell::RefCell, collections::HashMap, convert::TryFrom, fmt::Display, hash::Hash, io::Write,
-    mem::discriminant, ops, rc::Rc, vec,
+    cell::RefCell,
+    collections::HashMap,
+    convert::{TryFrom, TryInto},
+    fmt::Display,
+    hash::Hash,
+    io::Write,
+    mem::discriminant,
+    ops,
+    rc::Rc,
+    vec,
 };
 
 use rand::Rng;
@@ -203,31 +211,6 @@ impl Value {
             Value::Bool(b) => Value::Str(b.to_string()).into_cart(),
             Value::Abool(a) => Value::Str(a.to_string()).into_cart(),
             Value::Functio(f) => match f {
-                Functio::BfFunctio {
-                    instructions,
-                    tape_len,
-                } => {
-                    let mut cart: Cart = instructions
-                        .into_iter()
-                        .enumerate()
-                        .map(|(i, x)| {
-                            (
-                                Value::Int(i as i32 + 1),
-                                Rc::new(RefCell::new(
-                                    char::from_u32(x as u32)
-                                        .map(|x| Value::Str(x.to_string()))
-                                        .unwrap_or(Value::Nul),
-                                )),
-                            )
-                        })
-                        .collect();
-
-                    cart.insert(
-                        Value::Str("tapelen".to_owned()),
-                        Rc::new(RefCell::new(Value::Int(tape_len as _))),
-                    );
-                    cart
-                }
                 Functio::AbleFunctio { params, body } => {
                     let params: Cart = params
                         .into_iter()
@@ -264,6 +247,31 @@ impl Value {
 
                     cart
                 }
+                Functio::BfFunctio {
+                    instructions,
+                    tape_len,
+                } => {
+                    let mut cart: Cart = instructions
+                        .into_iter()
+                        .enumerate()
+                        .map(|(i, x)| {
+                            (
+                                Value::Int(i as i32 + 1),
+                                Rc::new(RefCell::new(
+                                    char::from_u32(x as u32)
+                                        .map(|x| Value::Str(x.to_string()))
+                                        .unwrap_or(Value::Nul),
+                                )),
+                            )
+                        })
+                        .collect();
+
+                    cart.insert(
+                        Value::Str("tapelen".to_owned()),
+                        Rc::new(RefCell::new(Value::Int(tape_len as _))),
+                    );
+                    cart
+                }
                 Functio::Eval(s) => Value::Str(s).into_cart(),
             },
             Value::Cart(c) => c,
@@ -276,10 +284,18 @@ impl ops::Add for Value {
 
     fn add(self, rhs: Self) -> Self::Output {
         match self {
-            Value::Nul => todo!(),
+            Value::Nul => match rhs {
+                Value::Nul => Value::Nul,
+                Value::Str(_) => Value::Str(self.to_string()) + rhs,
+                Value::Int(_) => Value::Int(self.into_i32()) + rhs,
+                Value::Bool(_) => Value::Bool(self.into_bool()) + rhs,
+                Value::Abool(_) => Value::Abool(self.into_abool()) + rhs,
+                Value::Functio(_) => Value::Functio(self.into_functio()) + rhs,
+                Value::Cart(_) => Value::Cart(self.into_cart()) + rhs,
+            },
             Value::Str(s) => Value::Str(format!("{}{}", s, rhs.to_string())),
-            Value::Int(i) => Value::Int(i.checked_add(rhs.into_i32()).unwrap_or(consts::ANSWER)),
-            Value::Bool(b) => Value::Bool(b ^ rhs.into_bool()),
+            Value::Int(i) => Value::Int(i.wrapping_add(rhs.into_i32())),
+            Value::Bool(b) => Value::Bool(b || rhs.into_bool()),
             Value::Abool(a) => Value::Abool({
                 let rhs = rhs.into_abool();
                 if a == rhs {
@@ -312,7 +328,28 @@ impl ops::Sub for Value {
     type Output = Value;
 
     fn sub(self, rhs: Self) -> Self::Output {
-        todo!()
+        match self {
+            Value::Nul => match rhs {
+                Value::Nul => Value::Nul,
+                Value::Str(_) => Value::Str(self.to_string()) - rhs,
+                Value::Int(_) => Value::Int(self.into_i32()) - rhs,
+                Value::Bool(_) => Value::Bool(self.into_bool()) - rhs,
+                Value::Abool(_) => Value::Abool(self.into_abool()) - rhs,
+                Value::Functio(_) => Value::Functio(self.into_functio()) - rhs,
+                Value::Cart(_) => Value::Cart(self.into_cart()) - rhs,
+            },
+            Value::Str(s) => Value::Str(s.replace(&rhs.to_string(), "")),
+            Value::Int(i) => Value::Int(i.wrapping_sub(rhs.into_i32())),
+            Value::Bool(b) => Value::Bool(b ^ rhs.into_bool()),
+            Value::Abool(_) => todo!(),
+            Value::Functio(_) => todo!(),
+            Value::Cart(c) => Value::Cart({
+                let rhs_cart = rhs.into_cart();
+                c.into_iter()
+                    .filter(|(k, v)| rhs_cart.get(k) != Some(v))
+                    .collect()
+            }),
+        }
     }
 }
 
@@ -320,7 +357,23 @@ impl ops::Mul for Value {
     type Output = Value;
 
     fn mul(self, rhs: Self) -> Self::Output {
-        todo!()
+        match self {
+            Value::Nul => match rhs {
+                Value::Nul => Value::Nul,
+                Value::Str(_) => Value::Str(self.to_string()) * rhs,
+                Value::Int(_) => Value::Int(self.into_i32()) * rhs,
+                Value::Bool(_) => Value::Bool(self.into_bool()) * rhs,
+                Value::Abool(_) => Value::Abool(self.into_abool()) * rhs,
+                Value::Functio(_) => Value::Functio(self.into_functio()) * rhs,
+                Value::Cart(_) => Value::Cart(self.into_cart()) * rhs,
+            },
+            Value::Str(s) => Value::Str(s.repeat(rhs.into_i32() as usize)),
+            Value::Int(i) => Value::Int(i.wrapping_mul(rhs.into_i32())),
+            Value::Bool(b) => Value::Bool(b && rhs.into_bool()),
+            Value::Abool(_) => todo!(),
+            Value::Functio(_) => todo!(),
+            Value::Cart(_) => todo!(),
+        }
     }
 }
 
@@ -328,7 +381,40 @@ impl ops::Div for Value {
     type Output = Value;
 
     fn div(self, rhs: Self) -> Self::Output {
-        todo!()
+        match self {
+            Value::Nul => match rhs {
+                Value::Nul => Value::Nul,
+                Value::Str(_) => Value::Str(self.to_string()) / rhs,
+                Value::Int(_) => Value::Int(self.into_i32()) / rhs,
+                Value::Bool(_) => Value::Bool(self.into_bool()) / rhs,
+                Value::Abool(_) => Value::Abool(self.into_abool()) / rhs,
+                Value::Functio(_) => Value::Functio(self.into_functio()) / rhs,
+                Value::Cart(_) => Value::Cart(self.into_cart()) / rhs,
+            },
+            Value::Str(s) => Value::Cart(
+                s.split(&rhs.to_string())
+                    .enumerate()
+                    .map(|(i, x)| {
+                        (
+                            Value::Int(i as i32 + 1),
+                            Rc::new(RefCell::new(Value::Str(x.to_owned()))),
+                        )
+                    })
+                    .collect(),
+            ),
+            Value::Int(i) => Value::Int({
+                let rhsi = rhs.into_i32();
+                if rhsi == 0 {
+                    consts::ANSWER
+                } else {
+                    i.wrapping_div(rhsi)
+                }
+            }),
+            Value::Bool(b) => Value::Bool(!(b && rhs.into_bool())),
+            Value::Abool(_) => todo!(),
+            Value::Functio(_) => todo!(),
+            Value::Cart(_) => todo!(),
+        }
     }
 }
 

From bd7209c004b5614814390b0c6d966035ab0430ba Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Mon, 30 Aug 2021 22:18:09 +0200
Subject: [PATCH 14/37] Removed And and Or ops because they aren't cursed
 enough

---
 ablescript/src/ast.rs       |  4 ----
 ablescript/src/interpret.rs |  2 --
 ablescript/src/lexer.rs     |  6 ------
 ablescript/src/parser.rs    |  4 +---
 ablescript/src/variables.rs | 16 ----------------
 5 files changed, 1 insertion(+), 31 deletions(-)

diff --git a/ablescript/src/ast.rs b/ablescript/src/ast.rs
index 0d68f11..61fe523 100644
--- a/ablescript/src/ast.rs
+++ b/ablescript/src/ast.rs
@@ -164,8 +164,6 @@ pub enum BinOpKind {
     Less,
     Equal,
     NotEqual,
-    And,
-    Or,
 }
 
 impl BinOpKind {
@@ -181,8 +179,6 @@ impl BinOpKind {
             Token::LessThan => Ok(Self::Less),
             Token::EqualEqual => Ok(Self::Equal),
             Token::NotEqual => Ok(Self::NotEqual),
-            Token::And => Ok(Self::And),
-            Token::Or => Ok(Self::Or),
             t => Err(crate::error::ErrorKind::UnexpectedToken(t)),
         }
     }
diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index 656583a..21e023a 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -149,8 +149,6 @@ impl ExecEnv {
                     Less => Value::Bool(lhs < rhs),
                     Equal => Value::Bool(lhs == rhs),
                     NotEqual => Value::Bool(lhs != rhs),
-                    And => lhs & rhs,
-                    Or => lhs | rhs,
                 }
             }
             Not(expr) => Bool(!self.eval_expr(expr)?.into_bool()),
diff --git a/ablescript/src/lexer.rs b/ablescript/src/lexer.rs
index 1ac49d6..c32d936 100644
--- a/ablescript/src/lexer.rs
+++ b/ablescript/src/lexer.rs
@@ -64,12 +64,6 @@ pub enum Token {
     #[token("!=")]
     NotEqual,
 
-    #[token("&")]
-    And,
-
-    #[token("|")]
-    Or,
-
     #[token("!|aint")] // also add aint as a not keyword
     Not,
 
diff --git a/ablescript/src/parser.rs b/ablescript/src/parser.rs
index 16c6733..e2873b0 100644
--- a/ablescript/src/parser.rs
+++ b/ablescript/src/parser.rs
@@ -209,9 +209,7 @@ impl<'source> Parser<'source> {
             | Token::EqualEqual
             | Token::NotEqual
             | Token::LessThan
-            | Token::GreaterThan
-            | Token::And
-            | Token::Or => Ok(Expr::new(
+            | Token::GreaterThan => Ok(Expr::new(
                 self.binop_flow(
                     BinOpKind::from_token(token).map_err(|e| Error::new(e, self.lexer.span()))?,
                     buf,
diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index 4e636a3..25b9217 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -459,22 +459,6 @@ impl PartialOrd for Value {
     }
 }
 
-impl ops::BitAnd for Value {
-    type Output = Value;
-
-    fn bitand(self, rhs: Self) -> Self::Output {
-        todo!()
-    }
-}
-
-impl ops::BitOr for Value {
-    type Output = Value;
-
-    fn bitor(self, rhs: Self) -> Self::Output {
-        todo!()
-    }
-}
-
 impl Display for Value {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {

From af2fe717fb3b26a9309630f64528d427cbc72cd7 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Mon, 30 Aug 2021 22:55:31 +0200
Subject: [PATCH 15/37] Not is now lexing and parsing correctly

---
 ablescript/src/interpret.rs | 8 ++++----
 ablescript/src/lexer.rs     | 2 +-
 ablescript/src/parser.rs    | 1 +
 ablescript/src/variables.rs | 8 ++++++++
 4 files changed, 14 insertions(+), 5 deletions(-)

diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index 21e023a..b22eedc 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -151,7 +151,7 @@ impl ExecEnv {
                     NotEqual => Value::Bool(lhs != rhs),
                 }
             }
-            Not(expr) => Bool(!self.eval_expr(expr)?.into_bool()),
+            Not(expr) => !self.eval_expr(expr)?,
             Literal(value) => value.clone(),
             ExprKind::Cart(members) => Value::Cart(
                 members
@@ -539,7 +539,7 @@ mod tests {
                 span: 1..1
             })
             .unwrap(),
-            Value::Int(42)
+            Value::Int(-2147483648)
         );
 
         // And the same for divide by zero.
@@ -547,7 +547,7 @@ mod tests {
             env.eval_expr(&Expr {
                 kind: ExprKind::BinOp {
                     lhs: Box::new(Expr {
-                        kind: ExprKind::Literal(Value::Int(1)),
+                        kind: ExprKind::Literal(Value::Int(84)),
                         span: 1..1,
                     }),
                     rhs: Box::new(Expr {
@@ -559,7 +559,7 @@ mod tests {
                 span: 1..1
             })
             .unwrap(),
-            Value::Int(42)
+            Value::Int(2)
         );
     }
 
diff --git a/ablescript/src/lexer.rs b/ablescript/src/lexer.rs
index c32d936..612d0e9 100644
--- a/ablescript/src/lexer.rs
+++ b/ablescript/src/lexer.rs
@@ -64,7 +64,7 @@ pub enum Token {
     #[token("!=")]
     NotEqual,
 
-    #[token("!|aint")] // also add aint as a not keyword
+    #[regex("!|aint")] // also add aint as a not keyword
     Not,
 
     // Keywords
diff --git a/ablescript/src/parser.rs b/ablescript/src/parser.rs
index e2873b0..49ade13 100644
--- a/ablescript/src/parser.rs
+++ b/ablescript/src/parser.rs
@@ -99,6 +99,7 @@ impl<'source> Parser<'source> {
             | Token::Abool(_)
             | Token::Bool(_)
             | Token::Nul
+            | Token::Not
             | Token::LeftBracket
             | Token::LeftParen => Ok(Stmt::new(
                 self.value_flow(token)?,
diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index 25b9217..8b2c788 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -418,6 +418,14 @@ impl ops::Div for Value {
     }
 }
 
+impl ops::Not for Value {
+    type Output = Value;
+
+    fn not(self) -> Self::Output {
+        todo!()
+    }
+}
+
 impl PartialEq for Value {
     fn eq(&self, other: &Self) -> bool {
         let other = other.clone();

From 70288ae4090154afdbe21c9222fb320d5bf2870b Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Mon, 30 Aug 2021 23:19:25 +0200
Subject: [PATCH 16/37] Implemented negation for most types

---
 ablescript/src/lexer.rs     |  2 +-
 ablescript/src/variables.rs | 26 ++++++++++++++++++++++++--
 2 files changed, 25 insertions(+), 3 deletions(-)

diff --git a/ablescript/src/lexer.rs b/ablescript/src/lexer.rs
index 612d0e9..e75414d 100644
--- a/ablescript/src/lexer.rs
+++ b/ablescript/src/lexer.rs
@@ -133,7 +133,7 @@ pub enum Token {
     String(String),
 
     /// Integer
-    #[regex(r"[0-9]+", get_int)]
+    #[regex(r"-?[0-9]+", get_int)]
     Integer(i32),
 
     /// A C-complaint identifier
diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index 8b2c788..8ff96ca 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -422,7 +422,23 @@ impl ops::Not for Value {
     type Output = Value;
 
     fn not(self) -> Self::Output {
-        todo!()
+        match self {
+            Value::Nul => Value::Nul,
+            Value::Str(s) => Value::Str(s.chars().rev().collect()),
+            Value::Int(i) => Value::Int(i.swap_bytes()),
+            Value::Bool(b) => Value::Bool(!b),
+            Value::Abool(a) => Value::Abool(match a {
+                Abool::Never => Abool::Always,
+                Abool::Sometimes => Abool::Sometimes,
+                Abool::Always => Abool::Never,
+            }),
+            Value::Functio(_) => todo!(),
+            Value::Cart(c) => Value::Cart(
+                c.into_iter()
+                    .map(|(k, v)| (v.borrow().clone(), Rc::new(RefCell::new(k))))
+                    .collect(),
+            ),
+        }
     }
 }
 
@@ -431,7 +447,13 @@ impl PartialEq for Value {
         let other = other.clone();
 
         match self {
-            Value::Nul => other == Value::Nul,
+            Value::Nul => {
+                if let Value::Nul = other {
+                    true
+                } else {
+                    false
+                }
+            }
             Value::Str(s) => *s == other.to_string(),
             Value::Int(i) => *i == other.into_i32(),
             Value::Bool(b) => *b == other.into_bool(),

From a33a3ddd7f0c98536e980b4c6591c7fd2c545a02 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Tue, 31 Aug 2021 00:41:05 +0200
Subject: [PATCH 17/37] All operations except functio ones are implemented -
 Aboolean logic - Cart division/multiplication

---
 ablescript/src/variables.rs | 74 +++++++++++++++++++++++--------------
 1 file changed, 46 insertions(+), 28 deletions(-)

diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index 8ff96ca..ee0bc87 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -186,7 +186,7 @@ impl Value {
                 params: vec![],
             },
             Value::Str(s) => Functio::Eval(s),
-            Value::Int(i) => todo!(),
+            Value::Int(_) => todo!(),
             Value::Bool(_) => todo!(),
             Value::Abool(_) => todo!(),
             Value::Functio(f) => f,
@@ -296,27 +296,10 @@ impl ops::Add for Value {
             Value::Str(s) => Value::Str(format!("{}{}", s, rhs.to_string())),
             Value::Int(i) => Value::Int(i.wrapping_add(rhs.into_i32())),
             Value::Bool(b) => Value::Bool(b || rhs.into_bool()),
-            Value::Abool(a) => Value::Abool({
-                let rhs = rhs.into_abool();
-                if a == rhs {
-                    a
-                } else if a == Abool::Sometimes {
-                    if rand::thread_rng().gen() {
-                        Abool::Sometimes
-                    } else {
-                        rhs
-                    }
-                } else if rhs == Abool::Sometimes {
-                    if rand::thread_rng().gen() {
-                        Abool::Sometimes
-                    } else {
-                        a
-                    }
-                } else {
-                    Abool::Sometimes
-                }
-            }),
-            Value::Functio(f) => Value::Functio(todo!()),
+            Value::Abool(_) => {
+                Value::Abool(Value::Int(self.into_i32().max(rhs.into_i32())).into_abool())
+            }
+            Value::Functio(_) => todo!(),
             Value::Cart(c) => {
                 Value::Cart(c.into_iter().chain(rhs.into_cart().into_iter()).collect())
             }
@@ -341,7 +324,7 @@ impl ops::Sub for Value {
             Value::Str(s) => Value::Str(s.replace(&rhs.to_string(), "")),
             Value::Int(i) => Value::Int(i.wrapping_sub(rhs.into_i32())),
             Value::Bool(b) => Value::Bool(b ^ rhs.into_bool()),
-            Value::Abool(_) => todo!(),
+            Value::Abool(_) => (self.clone() + rhs.clone()) * !(self * rhs),
             Value::Functio(_) => todo!(),
             Value::Cart(c) => Value::Cart({
                 let rhs_cart = rhs.into_cart();
@@ -370,9 +353,25 @@ impl ops::Mul for Value {
             Value::Str(s) => Value::Str(s.repeat(rhs.into_i32() as usize)),
             Value::Int(i) => Value::Int(i.wrapping_mul(rhs.into_i32())),
             Value::Bool(b) => Value::Bool(b && rhs.into_bool()),
-            Value::Abool(_) => todo!(),
+            Value::Abool(_) => {
+                Value::Abool(Value::Int(self.into_i32().min(rhs.into_i32())).into_abool())
+            }
             Value::Functio(_) => todo!(),
-            Value::Cart(_) => todo!(),
+            Value::Cart(c) => {
+                let rhsc = rhs.into_cart();
+
+                Value::Cart(
+                    c.into_iter()
+                        .map(|(k, v)| {
+                            if let Some(k) = rhsc.get(&k) {
+                                (k.borrow().clone(), v)
+                            } else {
+                                (k, v)
+                            }
+                        })
+                        .collect(),
+                )
+            }
         }
     }
 }
@@ -410,10 +409,29 @@ impl ops::Div for Value {
                     i.wrapping_div(rhsi)
                 }
             }),
-            Value::Bool(b) => Value::Bool(!(b && rhs.into_bool())),
-            Value::Abool(_) => todo!(),
+            Value::Bool(b) => Value::Bool(!b || rhs.into_bool()),
+            Value::Abool(_) => !self + rhs,
             Value::Functio(_) => todo!(),
-            Value::Cart(_) => todo!(),
+            Value::Cart(c) => {
+                let cart_len = c.len();
+                let chunk_len = rhs.into_i32() as usize;
+
+                Value::Cart(
+                    c.into_iter()
+                        .collect::<Vec<_>>()
+                        .chunks(cart_len / chunk_len + (cart_len % chunk_len != 0) as usize)
+                        .enumerate()
+                        .map(|(k, v)| {
+                            (
+                                Value::Int(k as i32 + 1),
+                                Rc::new(RefCell::new(Value::Cart(
+                                    v.into_iter().cloned().collect(),
+                                ))),
+                            )
+                        })
+                        .collect(),
+                )
+            }
         }
     }
 }

From 23f03e7f67656e667d92233104594298e685e561 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Wed, 1 Sep 2021 17:46:17 +0200
Subject: [PATCH 18/37] Clippy

---
 ablescript/src/interpret.rs |  5 ++---
 ablescript/src/variables.rs | 28 ++++++----------------------
 2 files changed, 8 insertions(+), 25 deletions(-)

diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index b22eedc..61a5065 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -21,7 +21,7 @@ use rand::random;
 use crate::{
     ast::{Expr, ExprKind, Iden, Stmt, StmtKind},
     base_55,
-    consts::{self, ablescript_consts},
+    consts::ablescript_consts,
     error::{Error, ErrorKind},
     variables::{Functio, Value, Variable},
 };
@@ -134,7 +134,6 @@ impl ExecEnv {
     fn eval_expr(&self, expr: &Expr) -> Result<Value, Error> {
         use crate::ast::BinOpKind::*;
         use crate::ast::ExprKind::*;
-        use Value::*;
 
         Ok(match &expr.kind {
             BinOp { lhs, rhs, kind } => {
@@ -345,7 +344,7 @@ impl ExecEnv {
                 res?;
             }
             Functio::Eval(code) => {
-                if args.len() != 0 {
+                if !args.is_empty() {
                     return Err(Error {
                         kind: ErrorKind::MismatchedArgumentError,
                         span: span.to_owned(),
diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index ee0bc87..23fb17a 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -1,14 +1,6 @@
 use std::{
-    cell::RefCell,
-    collections::HashMap,
-    convert::{TryFrom, TryInto},
-    fmt::Display,
-    hash::Hash,
-    io::Write,
-    mem::discriminant,
-    ops,
-    rc::Rc,
-    vec,
+    cell::RefCell, collections::HashMap, fmt::Display, hash::Hash, io::Write, mem::discriminant,
+    ops, rc::Rc, vec,
 };
 
 use rand::Rng;
@@ -424,9 +416,7 @@ impl ops::Div for Value {
                         .map(|(k, v)| {
                             (
                                 Value::Int(k as i32 + 1),
-                                Rc::new(RefCell::new(Value::Cart(
-                                    v.into_iter().cloned().collect(),
-                                ))),
+                                Rc::new(RefCell::new(Value::Cart(v.iter().cloned().collect()))),
                             )
                         })
                         .collect(),
@@ -465,13 +455,7 @@ impl PartialEq for Value {
         let other = other.clone();
 
         match self {
-            Value::Nul => {
-                if let Value::Nul = other {
-                    true
-                } else {
-                    false
-                }
-            }
+            Value::Nul => matches!(other, Value::Nul),
             Value::Str(s) => *s == other.to_string(),
             Value::Int(i) => *i == other.into_i32(),
             Value::Bool(b) => *b == other.into_bool(),
@@ -542,8 +526,8 @@ impl Display for Value {
             },
             Value::Cart(c) => {
                 write!(f, "[")?;
-                let mut cart_vec = c.into_iter().collect::<Vec<_>>();
-                cart_vec.sort_by(|x, y| x.0.partial_cmp(&y.0).unwrap_or(std::cmp::Ordering::Less));
+                let mut cart_vec = c.iter().collect::<Vec<_>>();
+                cart_vec.sort_by(|x, y| x.0.partial_cmp(y.0).unwrap_or(std::cmp::Ordering::Less));
 
                 for (key, value) in cart_vec {
                     write!(f, "{} <= {}, ", value.borrow(), key)?;

From fb16cb2ebbed019562237fd907f2a9f4ea7fa465 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Thu, 2 Sep 2021 18:35:33 +0200
Subject: [PATCH 19/37] Fixed division x/0 is now x/42 instead of 42 which
 makes it more confusing

---
 ablescript/src/variables.rs | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index 23fb17a..ca609a8 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -393,14 +393,10 @@ impl ops::Div for Value {
                     })
                     .collect(),
             ),
-            Value::Int(i) => Value::Int({
-                let rhsi = rhs.into_i32();
-                if rhsi == 0 {
-                    consts::ANSWER
-                } else {
-                    i.wrapping_div(rhsi)
-                }
-            }),
+            Value::Int(i) => Value::Int(i.wrapping_div(match rhs.into_i32() {
+                0 => consts::ANSWER,
+                rhsi => rhsi,
+            })),
             Value::Bool(b) => Value::Bool(!b || rhs.into_bool()),
             Value::Abool(_) => !self + rhs,
             Value::Functio(_) => todo!(),

From 1b9f8a61793825e6fb89e51d0ffd54176182d71a Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Thu, 2 Sep 2021 18:36:25 +0200
Subject: [PATCH 20/37] Variable name shortened

---
 ablescript/src/variables.rs | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index ca609a8..8aeb816 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -395,7 +395,7 @@ impl ops::Div for Value {
             ),
             Value::Int(i) => Value::Int(i.wrapping_div(match rhs.into_i32() {
                 0 => consts::ANSWER,
-                rhsi => rhsi,
+                x => x,
             })),
             Value::Bool(b) => Value::Bool(!b || rhs.into_bool()),
             Value::Abool(_) => !self + rhs,

From 7673b64a7149e422cb42b591a2561e1d58ecfe4b Mon Sep 17 00:00:00 2001
From: Alex Bethel <abethel@cs.nmt.edu>
Date: Sat, 4 Sep 2021 10:54:53 -0600
Subject: [PATCH 21/37] Improve consistency of code & comments

Changed all `&str.to_string()` into `&str.to_owned()`, and made the
grammar of the `Value::into_*` comments uniform.
---
 ablescript/src/interpret.rs |  2 +-
 ablescript/src/parser.rs    | 20 ++++++++++----------
 ablescript/src/variables.rs |  7 ++++---
 3 files changed, 15 insertions(+), 14 deletions(-)

diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index 61a5065..516b681 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -201,7 +201,7 @@ impl ExecEnv {
                 self.decl_var(
                     &iden.iden,
                     Value::Functio(Functio::AbleFunctio {
-                        params: params.iter().map(|iden| iden.iden.to_string()).collect(),
+                        params: params.iter().map(|iden| iden.iden.to_owned()).collect(),
                         body: body.block.to_owned(),
                     }),
                 );
diff --git a/ablescript/src/parser.rs b/ablescript/src/parser.rs
index 49ade13..e0debe2 100644
--- a/ablescript/src/parser.rs
+++ b/ablescript/src/parser.rs
@@ -558,7 +558,7 @@ mod tests {
                             rhs: Box::new(Expr {
                                 kind: ExprKind::BinOp {
                                     lhs: Box::new(Expr {
-                                        kind: ExprKind::Variable("a".to_string()),
+                                        kind: ExprKind::Variable("a".to_owned()),
                                         span: 5..6,
                                     }),
                                     rhs: Box::new(Expr {
@@ -594,7 +594,7 @@ mod tests {
         let expected = &[Stmt {
             kind: StmtKind::Var {
                 iden: Iden {
-                    iden: "a".to_string(),
+                    iden: "a".to_owned(),
                     span: 4..5,
                 },
                 init: Some(Expr {
@@ -631,7 +631,7 @@ mod tests {
                 body: Block {
                     block: vec![Stmt {
                         kind: StmtKind::Print(Expr {
-                            kind: ExprKind::Literal(Value::Str("Buy Able products!".to_string())),
+                            kind: ExprKind::Literal(Value::Str("Buy Able products!".to_owned())),
                             span: 19..39,
                         }),
                         span: 19..46,
@@ -651,17 +651,17 @@ mod tests {
         let expected = &[Stmt {
             kind: StmtKind::Var {
                 iden: Iden {
-                    iden: "script".to_string(),
+                    iden: "script".to_owned(),
                     span: 13..17,
                 },
                 init: Some(Expr {
                     kind: ExprKind::BinOp {
                         lhs: Box::new(Expr {
-                            kind: ExprKind::Literal(Value::Str("script".to_string())),
+                            kind: ExprKind::Literal(Value::Str("script".to_owned())),
                             span: 20..26,
                         }),
                         rhs: Box::new(Expr {
-                            kind: ExprKind::Variable("script".to_string()),
+                            kind: ExprKind::Variable("script".to_owned()),
                             span: 29..33,
                         }),
                         kind: BinOpKind::Add,
@@ -684,7 +684,7 @@ mod tests {
                 kind: ExprKind::Cart(vec![
                     (
                         Expr {
-                            kind: ExprKind::Literal(Value::Str("able".to_string())),
+                            kind: ExprKind::Literal(Value::Str("able".to_owned())),
                             span: 1..7,
                         },
                         Expr {
@@ -694,7 +694,7 @@ mod tests {
                     ),
                     (
                         Expr {
-                            kind: ExprKind::Literal(Value::Str("script".to_string())),
+                            kind: ExprKind::Literal(Value::Str("script".to_owned())),
                             span: 14..22,
                         },
                         Expr {
@@ -731,11 +731,11 @@ mod tests {
                     expr: Box::new(Expr {
                         kind: ExprKind::Cart(vec![(
                             Expr {
-                                kind: ExprKind::Literal(Value::Str("able".to_string())),
+                                kind: ExprKind::Literal(Value::Str("able".to_owned())),
                                 span: 1..7,
                             },
                             Expr {
-                                kind: ExprKind::Literal(Value::Str("ablecorp".to_string())),
+                                kind: ExprKind::Literal(Value::Str("ablecorp".to_owned())),
                                 span: 11..21,
                             },
                         )]),
diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index 8aeb816..fb663a5 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -113,7 +113,7 @@ impl Value {
         }
     }
 
-    /// Coerce a Value to a boolean. The conversion cannot fail.
+    /// Coerce a value to a boolean.
     pub fn into_bool(self) -> bool {
         match self {
             Value::Abool(b) => b.into(),
@@ -130,7 +130,7 @@ impl Value {
         }
     }
 
-    /// Coerce a Value to an aboolean
+    /// Coerce a value to an aboolean.
     pub fn into_abool(self) -> Abool {
         match self {
             Value::Nul => Abool::Never,
@@ -170,7 +170,7 @@ impl Value {
         }
     }
 
-    /// Coerce a Value to a functio
+    /// Coerce a value to a functio.
     pub fn into_functio(self) -> Functio {
         match self {
             Value::Nul => Functio::AbleFunctio {
@@ -186,6 +186,7 @@ impl Value {
         }
     }
 
+    /// Coerce a value into a cart.
     pub fn into_cart(self) -> Cart {
         match self {
             Value::Nul => HashMap::new(),

From d229c3d3c35713b037724d7d2c8e3ab777f172f3 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Mon, 4 Oct 2021 23:00:18 +0200
Subject: [PATCH 22/37] Renamed `Iden` to `Ident`

---
 ablescript/src/ast.rs       | 32 ++++++++---------
 ablescript/src/interpret.rs | 70 ++++++++++++++++++-------------------
 ablescript/src/lexer.rs     |  4 +--
 ablescript/src/parser.rs    | 48 ++++++++++++-------------
 4 files changed, 77 insertions(+), 77 deletions(-)

diff --git a/ablescript/src/ast.rs b/ablescript/src/ast.rs
index 61fe523..8e654ed 100644
--- a/ablescript/src/ast.rs
+++ b/ablescript/src/ast.rs
@@ -15,26 +15,26 @@ use crate::variables::Value;
 type Span = std::ops::Range<usize>;
 
 #[derive(Debug, Clone)]
-pub struct Iden {
-    pub iden: String,
+pub struct Ident {
+    pub ident: String,
     pub span: Span,
 }
 
-impl Iden {
-    pub fn new(iden: String, span: Span) -> Self {
-        Self { iden, span }
+impl Ident {
+    pub fn new(ident: String, span: Span) -> Self {
+        Self { ident, span }
     }
 }
 
-impl PartialEq for Iden {
+impl PartialEq for Ident {
     fn eq(&self, other: &Self) -> bool {
-        self.iden == other.iden
+        self.ident == other.ident
     }
 }
 
-impl Hash for Iden {
+impl Hash for Ident {
     fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
-        self.iden.hash(state)
+        self.ident.hash(state)
     }
 }
 
@@ -76,21 +76,21 @@ pub enum StmtKind {
     HopBack,
 
     Var {
-        iden: Iden,
+        ident: Ident,
         init: Option<Expr>,
     },
     Assign {
-        iden: Iden,
+        ident: Ident,
         value: Expr,
     },
 
     Functio {
-        iden: Iden,
-        params: Vec<Iden>,
+        ident: Ident,
+        params: Vec<Ident>,
         body: Block,
     },
     BfFunctio {
-        iden: Iden,
+        ident: Ident,
         tape_len: Option<Expr>,
         code: Vec<u8>,
     },
@@ -99,8 +99,8 @@ pub enum StmtKind {
         args: Vec<Expr>,
     },
     Print(Expr),
-    Read(Iden),
-    Melo(Iden),
+    Read(Ident),
+    Melo(Ident),
     Rlyeh,
     Rickroll,
 }
diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index 516b681..ab58a7e 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -19,7 +19,7 @@ use std::{
 use rand::random;
 
 use crate::{
-    ast::{Expr, ExprKind, Iden, Stmt, StmtKind},
+    ast::{Expr, ExprKind, Ident, Stmt, StmtKind},
     base_55,
     consts::ablescript_consts,
     error::{Error, ErrorKind},
@@ -175,9 +175,9 @@ impl ExecEnv {
             }
 
             // TODO: not too happy with constructing an artificial
-            // Iden here.
-            Variable(name) => self.get_var(&Iden {
-                iden: name.to_owned(),
+            // Ident here.
+            Variable(name) => self.get_var(&Ident {
+                ident: name.to_owned(),
                 span: expr.span.clone(),
             })?,
         })
@@ -189,30 +189,30 @@ impl ExecEnv {
             StmtKind::Print(expr) => {
                 println!("{}", self.eval_expr(expr)?);
             }
-            StmtKind::Var { iden, init } => {
+            StmtKind::Var { ident, init } => {
                 let init = match init {
                     Some(e) => self.eval_expr(e)?,
                     None => Value::Nul,
                 };
 
-                self.decl_var(&iden.iden, init);
+                self.decl_var(&ident.ident, init);
             }
-            StmtKind::Functio { iden, params, body } => {
+            StmtKind::Functio { ident, params, body } => {
                 self.decl_var(
-                    &iden.iden,
+                    &ident.ident,
                     Value::Functio(Functio::AbleFunctio {
-                        params: params.iter().map(|iden| iden.iden.to_owned()).collect(),
+                        params: params.iter().map(|ident| ident.ident.to_owned()).collect(),
                         body: body.block.to_owned(),
                     }),
                 );
             }
             StmtKind::BfFunctio {
-                iden,
+                ident,
                 tape_len,
                 code,
             } => {
                 self.decl_var(
-                    &iden.iden,
+                    &ident.ident,
                     Value::Functio(Functio::BfFunctio {
                         instructions: code.to_owned(),
                         tape_len: tape_len
@@ -240,9 +240,9 @@ impl ExecEnv {
                     HaltStatus::Hopback(_) => continue,
                 }
             },
-            StmtKind::Assign { iden, value } => {
+            StmtKind::Assign { ident, value } => {
                 let value = self.eval_expr(value)?;
-                self.get_var_mut(iden)?.value.replace(value);
+                self.get_var_mut(ident)?.value.replace(value);
             }
             StmtKind::Break => {
                 return Ok(HaltStatus::Break(stmt.span.clone()));
@@ -250,8 +250,8 @@ impl ExecEnv {
             StmtKind::HopBack => {
                 return Ok(HaltStatus::Hopback(stmt.span.clone()));
             }
-            StmtKind::Melo(iden) => {
-                self.get_var_mut(iden)?.melo = true;
+            StmtKind::Melo(ident) => {
+                self.get_var_mut(ident)?.melo = true;
             }
             StmtKind::Rlyeh => {
                 // Maybe print a creepy error message or something
@@ -263,14 +263,14 @@ impl ExecEnv {
                     .write_all(include_str!("rickroll").as_bytes())
                     .expect("Failed to write to stdout");
             }
-            StmtKind::Read(iden) => {
+            StmtKind::Read(ident) => {
                 let mut value = 0;
                 for _ in 0..READ_BITS {
                     value <<= 1;
                     value += self.get_bit()? as i32;
                 }
 
-                self.get_var_mut(iden)?.value.replace(Value::Int(value));
+                self.get_var_mut(ident)?.value.replace(Value::Int(value));
             }
         }
 
@@ -287,8 +287,8 @@ impl ExecEnv {
             .iter()
             .map(|arg| {
                 if let ExprKind::Variable(name) = &arg.kind {
-                    self.get_var_rc(&Iden {
-                        iden: name.to_owned(),
+                    self.get_var_rc(&Ident {
+                        ident: name.to_owned(),
                         span: arg.span.clone(),
                     })
                 } else {
@@ -380,9 +380,9 @@ impl ExecEnv {
 
     /// Get the value of a variable. Throw an error if the variable is
     /// inaccessible or banned.
-    fn get_var(&self, name: &Iden) -> Result<Value, Error> {
+    fn get_var(&self, name: &Ident) -> Result<Value, Error> {
         // One-letter names are reserved as base55 numbers.
-        let mut chars = name.iden.chars();
+        let mut chars = name.ident.chars();
         if let (Some(first), None) = (chars.next(), chars.next()) {
             return Ok(Value::Int(base_55::char2num(first)));
         }
@@ -393,20 +393,20 @@ impl ExecEnv {
             .stack
             .iter()
             .rev()
-            .find_map(|scope| scope.variables.get(&name.iden))
+            .find_map(|scope| scope.variables.get(&name.ident))
         {
             Some(var) => {
                 if !var.melo {
                     Ok(var.value.borrow().clone())
                 } else {
                     Err(Error {
-                        kind: ErrorKind::MeloVariable(name.iden.to_owned()),
+                        kind: ErrorKind::MeloVariable(name.ident.to_owned()),
                         span: name.span.clone(),
                     })
                 }
             }
             None => Err(Error {
-                kind: ErrorKind::UnknownVariable(name.iden.to_owned()),
+                kind: ErrorKind::UnknownVariable(name.ident.to_owned()),
                 span: name.span.clone(),
             }),
         }
@@ -414,27 +414,27 @@ impl ExecEnv {
 
     /// Get a mutable reference to a variable. Throw an error if the
     /// variable is inaccessible or banned.
-    fn get_var_mut(&mut self, name: &Iden) -> Result<&mut Variable, Error> {
+    fn get_var_mut(&mut self, name: &Ident) -> Result<&mut Variable, Error> {
         // This function has a lot of duplicated code with `get_var`,
         // which I feel like is a bad sign...
         match self
             .stack
             .iter_mut()
             .rev()
-            .find_map(|scope| scope.variables.get_mut(&name.iden))
+            .find_map(|scope| scope.variables.get_mut(&name.ident))
         {
             Some(var) => {
                 if !var.melo {
                     Ok(var)
                 } else {
                     Err(Error {
-                        kind: ErrorKind::MeloVariable(name.iden.to_owned()),
+                        kind: ErrorKind::MeloVariable(name.ident.to_owned()),
                         span: name.span.clone(),
                     })
                 }
             }
             None => Err(Error {
-                kind: ErrorKind::UnknownVariable(name.iden.to_owned()),
+                kind: ErrorKind::UnknownVariable(name.ident.to_owned()),
                 span: name.span.clone(),
             }),
         }
@@ -442,7 +442,7 @@ impl ExecEnv {
 
     /// Get an Rc'd pointer to the value of a variable. Throw an error
     /// if the variable is inaccessible or banned.
-    fn get_var_rc(&mut self, name: &Iden) -> Result<Rc<RefCell<Value>>, Error> {
+    fn get_var_rc(&mut self, name: &Ident) -> Result<Rc<RefCell<Value>>, Error> {
         Ok(self.get_var_mut(name)?.value.clone())
     }
 
@@ -584,8 +584,8 @@ mod tests {
         // Declaring and reading from a variable.
         eval(&mut env, "var foo = 32; var bar = foo + 1;").unwrap();
         assert_eq!(
-            env.get_var(&Iden {
-                iden: "bar".to_owned(),
+            env.get_var(&Ident {
+                ident: "bar".to_owned(),
                 span: 1..1,
             })
             .unwrap(),
@@ -595,8 +595,8 @@ mod tests {
         // Assigning an existing variable.
         eval(&mut env, "foo = \"hi\";").unwrap();
         assert_eq!(
-            env.get_var(&Iden {
-                iden: "foo".to_owned(),
+            env.get_var(&Ident {
+                ident: "foo".to_owned(),
                 span: 1..1,
             })
             .unwrap(),
@@ -621,8 +621,8 @@ mod tests {
         .unwrap();
 
         assert_eq!(
-            env.get_var(&Iden {
-                iden: "foo".to_owned(),
+            env.get_var(&Ident {
+                ident: "foo".to_owned(),
                 span: 1..1,
             })
             .unwrap(),
diff --git a/ablescript/src/lexer.rs b/ablescript/src/lexer.rs
index e75414d..24ee265 100644
--- a/ablescript/src/lexer.rs
+++ b/ablescript/src/lexer.rs
@@ -137,7 +137,7 @@ pub enum Token {
     Integer(i32),
 
     /// A C-complaint identifier
-    #[regex(r"[a-zA-Z_][a-zA-Z_0-9]*", get_iden)]
+    #[regex(r"[a-zA-Z_][a-zA-Z_0-9]*", get_ident)]
     Identifier(String),
 
     #[regex(r"owo .*")]
@@ -172,7 +172,7 @@ fn get_abool(lexer: &mut Lexer<Token>) -> Option<Abool> {
     }
 }
 
-fn get_iden(lexer: &mut Lexer<Token>) -> String {
+fn get_ident(lexer: &mut Lexer<Token>) -> String {
     lexer.slice().to_owned()
 }
 
diff --git a/ablescript/src/parser.rs b/ablescript/src/parser.rs
index e0debe2..f07039d 100644
--- a/ablescript/src/parser.rs
+++ b/ablescript/src/parser.rs
@@ -131,13 +131,13 @@ impl<'source> Parser<'source> {
     }
 
     /// Get an Identifier
-    fn get_iden(&mut self) -> Result<Iden, Error> {
+    fn get_ident(&mut self) -> Result<Ident, Error> {
         match self.checked_next()? {
-            Token::Identifier(iden) => Ok(Iden {
-                iden: if self.tdark {
-                    iden.replace("lang", "script")
+            Token::Identifier(ident) => Ok(Ident {
+                ident: if self.tdark {
+                    ident.replace("lang", "script")
                 } else {
-                    iden
+                    ident
                 },
                 span: self.lexer.span(),
             }),
@@ -356,12 +356,12 @@ impl<'source> Parser<'source> {
                 // Variable Assignment
                 Token::Equal => {
                     if let Some(Expr {
-                        kind: ExprKind::Variable(iden),
+                        kind: ExprKind::Variable(ident),
                         span,
                     }) = buf
                     {
                         break StmtKind::Assign {
-                            iden: Iden::new(iden, span),
+                            ident: Ident::new(ident, span),
                             value: self.expr_flow(Token::Semicolon)?,
                         };
                     }
@@ -370,11 +370,11 @@ impl<'source> Parser<'source> {
                 // Read input
                 Token::Read => {
                     if let Some(Expr {
-                        kind: ExprKind::Variable(iden),
+                        kind: ExprKind::Variable(ident),
                         span,
                     }) = buf
                     {
-                        break self.semi_terminated(StmtKind::Read(Iden::new(iden, span)))?;
+                        break self.semi_terminated(StmtKind::Read(Ident::new(ident, span)))?;
                     }
                 }
 
@@ -400,9 +400,9 @@ impl<'source> Parser<'source> {
 
     /// Parse functio flow
     ///
-    /// functio $iden (a, b, c) { ... }
+    /// functio $ident (a, b, c) { ... }
     fn functio_flow(&mut self) -> Result<StmtKind, Error> {
-        let iden = self.get_iden()?;
+        let ident = self.get_ident()?;
 
         self.require(Token::LeftParen)?;
 
@@ -411,7 +411,7 @@ impl<'source> Parser<'source> {
             match self.checked_next()? {
                 Token::RightParen => break,
                 Token::Identifier(i) => {
-                    params.push(Iden::new(i, self.lexer.span()));
+                    params.push(Ident::new(i, self.lexer.span()));
 
                     // Require comma (next) or right paren (end) after identifier
                     match self.checked_next()? {
@@ -431,14 +431,14 @@ impl<'source> Parser<'source> {
 
         let body = self.get_block()?;
 
-        Ok(StmtKind::Functio { iden, params, body })
+        Ok(StmtKind::Functio { ident, params, body })
     }
 
     /// Parse BF function declaration
     ///
-    /// `bff $iden ([tapelen]) { ... }`
+    /// `bff $ident ([tapelen]) { ... }`
     fn bff_flow(&mut self) -> Result<StmtKind, Error> {
-        let iden = self.get_iden()?;
+        let ident = self.get_ident()?;
 
         let tape_len = match self.checked_next()? {
             Token::LeftParen => {
@@ -472,7 +472,7 @@ impl<'source> Parser<'source> {
         }
 
         Ok(StmtKind::BfFunctio {
-            iden,
+            ident,
             tape_len,
             code,
         })
@@ -513,20 +513,20 @@ impl<'source> Parser<'source> {
 
     /// Parse variable declaration
     fn var_flow(&mut self) -> Result<StmtKind, Error> {
-        let iden = self.get_iden()?;
+        let ident = self.get_ident()?;
         let init = match self.checked_next()? {
             Token::Equal => Some(self.expr_flow(Token::Semicolon)?),
             Token::Semicolon => None,
             t => return Err(Error::new(ErrorKind::UnexpectedToken(t), self.lexer.span())),
         };
 
-        Ok(StmtKind::Var { iden, init })
+        Ok(StmtKind::Var { ident, init })
     }
 
     /// Parse Melo flow
     fn melo_flow(&mut self) -> Result<StmtKind, Error> {
-        let iden = self.get_iden()?;
-        self.semi_terminated(StmtKind::Melo(iden))
+        let ident = self.get_ident()?;
+        self.semi_terminated(StmtKind::Melo(ident))
     }
 
     /// Parse loop flow
@@ -593,8 +593,8 @@ mod tests {
         let code = r#"var a = 42;"#;
         let expected = &[Stmt {
             kind: StmtKind::Var {
-                iden: Iden {
-                    iden: "a".to_owned(),
+                ident: Ident {
+                    ident: "a".to_owned(),
                     span: 4..5,
                 },
                 init: Some(Expr {
@@ -650,8 +650,8 @@ mod tests {
         let code = r#"T-Dark { var lang = "lang" + lang; }"#;
         let expected = &[Stmt {
             kind: StmtKind::Var {
-                iden: Iden {
-                    iden: "script".to_owned(),
+                ident: Ident {
+                    ident: "script".to_owned(),
                     span: 13..17,
                 },
                 init: Some(Expr {

From 1a5d2edee1d2b1680cc58742e946105439fc4c9f Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Mon, 4 Oct 2021 23:03:23 +0200
Subject: [PATCH 23/37] Generalised some lexer functions

---
 ablescript/src/lexer.rs | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/ablescript/src/lexer.rs b/ablescript/src/lexer.rs
index 24ee265..a6c5940 100644
--- a/ablescript/src/lexer.rs
+++ b/ablescript/src/lexer.rs
@@ -117,7 +117,7 @@ pub enum Token {
 
     // Literals
     /// True, False
-    #[regex("true|false", get_bool)]
+    #[regex("true|false", get_value)]
     Bool(bool),
 
     /// Always, Sometimes, Never
@@ -133,7 +133,7 @@ pub enum Token {
     String(String),
 
     /// Integer
-    #[regex(r"-?[0-9]+", get_int)]
+    #[regex(r"-?[0-9]+", get_value)]
     Integer(i32),
 
     /// A C-complaint identifier
@@ -151,11 +151,7 @@ pub enum Token {
     Error,
 }
 
-fn get_bool(lexer: &mut Lexer<Token>) -> Option<bool> {
-    lexer.slice().parse().ok()
-}
-
-fn get_int(lexer: &mut Lexer<Token>) -> Option<i32> {
+fn get_value<T: std::str::FromStr>(lexer: &mut Lexer<Token>) -> Option<T> {
     lexer.slice().parse().ok()
 }
 

From ea79e805f2a4856cfeeab0d8da23bc73c6e3c229 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Tue, 12 Oct 2021 22:14:20 +0200
Subject: [PATCH 24/37] Added Assignable support in parser / AST

---
 ablescript/src/ast.rs       | 14 ++++++++++-
 ablescript/src/interpret.rs | 11 ++++++---
 ablescript/src/parser.rs    | 49 +++++++++++++++++++++++++++++++------
 3 files changed, 63 insertions(+), 11 deletions(-)

diff --git a/ablescript/src/ast.rs b/ablescript/src/ast.rs
index 8e654ed..e11cb33 100644
--- a/ablescript/src/ast.rs
+++ b/ablescript/src/ast.rs
@@ -38,6 +38,18 @@ impl Hash for Ident {
     }
 }
 
+#[derive(Debug, PartialEq, Clone, Hash)]
+pub struct Assignable {
+    pub ident: Ident,
+    pub kind: AssignableKind,
+}
+
+#[derive(Debug, PartialEq, Clone, Hash)]
+pub enum AssignableKind {
+    Variable,
+    Cart { indices: Vec<Expr> },
+}
+
 #[derive(Debug, PartialEq, Clone, Hash)]
 pub struct Block {
     pub block: Vec<Stmt>,
@@ -80,7 +92,7 @@ pub enum StmtKind {
         init: Option<Expr>,
     },
     Assign {
-        ident: Ident,
+        assignable: Assignable,
         value: Expr,
     },
 
diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index ab58a7e..f9b10e7 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -197,7 +197,11 @@ impl ExecEnv {
 
                 self.decl_var(&ident.ident, init);
             }
-            StmtKind::Functio { ident, params, body } => {
+            StmtKind::Functio {
+                ident,
+                params,
+                body,
+            } => {
                 self.decl_var(
                     &ident.ident,
                     Value::Functio(Functio::AbleFunctio {
@@ -240,9 +244,10 @@ impl ExecEnv {
                     HaltStatus::Hopback(_) => continue,
                 }
             },
-            StmtKind::Assign { ident, value } => {
+            StmtKind::Assign { assignable, value } => {
+                // TODO: Assigning to carts
                 let value = self.eval_expr(value)?;
-                self.get_var_mut(ident)?.value.replace(value);
+                self.get_var_mut(&assignable.ident)?.value.replace(value);
             }
             StmtKind::Break => {
                 return Ok(HaltStatus::Break(stmt.span.clone()));
diff --git a/ablescript/src/parser.rs b/ablescript/src/parser.rs
index f07039d..f01a9da 100644
--- a/ablescript/src/parser.rs
+++ b/ablescript/src/parser.rs
@@ -355,15 +355,25 @@ impl<'source> Parser<'source> {
 
                 // Variable Assignment
                 Token::Equal => {
-                    if let Some(Expr {
-                        kind: ExprKind::Variable(ident),
-                        span,
-                    }) = buf
-                    {
+                    let assignable = buf.take().and_then(|buf| match buf.kind {
+                        ExprKind::Variable(ident) => Some(Assignable {
+                            ident: Ident::new(ident, buf.span),
+                            kind: AssignableKind::Variable,
+                        }),
+                        ExprKind::Index { expr, index } => self.cart_assignable_flow(*expr, *index),
+                        _ => None,
+                    });
+
+                    if let Some(assignable) = assignable {
                         break StmtKind::Assign {
-                            ident: Ident::new(ident, span),
+                            assignable,
                             value: self.expr_flow(Token::Semicolon)?,
                         };
+                    } else {
+                        return Err(Error::new(
+                            ErrorKind::UnexpectedToken(Token::Equal),
+                            self.lexer.span(),
+                        ));
                     }
                 }
 
@@ -385,6 +395,27 @@ impl<'source> Parser<'source> {
         Ok(r)
     }
 
+    /// Parse Cart Assignable flow
+    fn cart_assignable_flow(&mut self, mut buf: Expr, index: Expr) -> Option<Assignable> {
+        let mut indices = vec![index];
+        let ident = loop {
+            match buf.kind {
+                ExprKind::Variable(ident) => break ident,
+                ExprKind::Index { expr, index } => {
+                    indices.push(*index);
+                    buf = *expr;
+                }
+                _ => return None,
+            }
+        };
+
+        indices.reverse();
+        Some(Assignable {
+            ident: Ident::new(ident, buf.span),
+            kind: AssignableKind::Cart { indices },
+        })
+    }
+
     /// Parse If flow
     ///
     /// Consists of condition and block, there is no else
@@ -431,7 +462,11 @@ impl<'source> Parser<'source> {
 
         let body = self.get_block()?;
 
-        Ok(StmtKind::Functio { ident, params, body })
+        Ok(StmtKind::Functio {
+            ident,
+            params,
+            body,
+        })
     }
 
     /// Parse BF function declaration

From cce392aaaa458a6579c90d1895636fe679488989 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Tue, 12 Oct 2021 22:22:33 +0200
Subject: [PATCH 25/37] improvement

---
 ablescript/src/interpret.rs | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index f9b10e7..d778464 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -245,9 +245,14 @@ impl ExecEnv {
                 }
             },
             StmtKind::Assign { assignable, value } => {
-                // TODO: Assigning to carts
                 let value = self.eval_expr(value)?;
-                self.get_var_mut(&assignable.ident)?.value.replace(value);
+                match &assignable.kind {
+                    crate::ast::AssignableKind::Variable => {
+                        &self.get_var_mut(&assignable.ident)?.value
+                    }
+                    crate::ast::AssignableKind::Cart { indices } => todo!("assigning to carts"),
+                }
+                .replace(value);
             }
             StmtKind::Break => {
                 return Ok(HaltStatus::Break(stmt.span.clone()));

From 990e2806f127d53d775d974b227307f10e1c9ec8 Mon Sep 17 00:00:00 2001
From: Alex Bethel <abethel@cs.nmt.edu>
Date: Tue, 12 Oct 2021 14:33:23 -0600
Subject: [PATCH 26/37] Sort of fix cart assignments

---
 ablescript/src/interpret.rs | 19 +++++++++++++------
 1 file changed, 13 insertions(+), 6 deletions(-)

diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index d778464..33bb740 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -19,7 +19,7 @@ use std::{
 use rand::random;
 
 use crate::{
-    ast::{Expr, ExprKind, Ident, Stmt, StmtKind},
+    ast::{AssignableKind, Expr, ExprKind, Ident, Stmt, StmtKind},
     base_55,
     consts::ablescript_consts,
     error::{Error, ErrorKind},
@@ -246,13 +246,20 @@ impl ExecEnv {
             },
             StmtKind::Assign { assignable, value } => {
                 let value = self.eval_expr(value)?;
-                match &assignable.kind {
-                    crate::ast::AssignableKind::Variable => {
-                        &self.get_var_mut(&assignable.ident)?.value
+                match assignable.kind {
+                    AssignableKind::Variable => {
+                        &self.get_var_mut(&assignable.ident)?.value.replace(value);
+                    }
+                    AssignableKind::Cart { ref indices } => {
+                        let mut cell = self.get_var_rc(&assignable.ident)?;
+                        for index in indices {
+                            let index = self.eval_expr(index)?;
+                            let value = cell.borrow().to_owned();
+                            cell = Rc::clone(value.into_cart().get(&index).unwrap());
+                        }
+                        cell.replace(value);
                     }
-                    crate::ast::AssignableKind::Cart { indices } => todo!("assigning to carts"),
                 }
-                .replace(value);
             }
             StmtKind::Break => {
                 return Ok(HaltStatus::Break(stmt.span.clone()));

From 3cff0da70aaa9d9a3b21e8d3a7a2055fa48a658b Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Wed, 13 Oct 2021 13:20:23 +0200
Subject: [PATCH 27/37] Change Cart AssignableKind to Index.

---
 ablescript/src/ast.rs       | 2 +-
 ablescript/src/interpret.rs | 4 ++--
 ablescript/src/parser.rs    | 2 +-
 3 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/ablescript/src/ast.rs b/ablescript/src/ast.rs
index e11cb33..67cd235 100644
--- a/ablescript/src/ast.rs
+++ b/ablescript/src/ast.rs
@@ -47,7 +47,7 @@ pub struct Assignable {
 #[derive(Debug, PartialEq, Clone, Hash)]
 pub enum AssignableKind {
     Variable,
-    Cart { indices: Vec<Expr> },
+    Index { indices: Vec<Expr> },
 }
 
 #[derive(Debug, PartialEq, Clone, Hash)]
diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index 33bb740..1c7f096 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -248,9 +248,9 @@ impl ExecEnv {
                 let value = self.eval_expr(value)?;
                 match assignable.kind {
                     AssignableKind::Variable => {
-                        &self.get_var_mut(&assignable.ident)?.value.replace(value);
+                        self.get_var_mut(&assignable.ident)?.value.replace(value);
                     }
-                    AssignableKind::Cart { ref indices } => {
+                    AssignableKind::Index { ref indices } => {
                         let mut cell = self.get_var_rc(&assignable.ident)?;
                         for index in indices {
                             let index = self.eval_expr(index)?;
diff --git a/ablescript/src/parser.rs b/ablescript/src/parser.rs
index f01a9da..d850f60 100644
--- a/ablescript/src/parser.rs
+++ b/ablescript/src/parser.rs
@@ -412,7 +412,7 @@ impl<'source> Parser<'source> {
         indices.reverse();
         Some(Assignable {
             ident: Ident::new(ident, buf.span),
-            kind: AssignableKind::Cart { indices },
+            kind: AssignableKind::Index { indices },
         })
     }
 

From a82a9d7b79200c372bf2d317e6a2be05f6900a97 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Thu, 21 Oct 2021 20:51:24 +0200
Subject: [PATCH 28/37] Moved Assignable creation functions

---
 ablescript/src/ast.rs    | 33 +++++++++++++++++++++++++++++++++
 ablescript/src/parser.rs | 32 +-------------------------------
 2 files changed, 34 insertions(+), 31 deletions(-)

diff --git a/ablescript/src/ast.rs b/ablescript/src/ast.rs
index 67cd235..fa30420 100644
--- a/ablescript/src/ast.rs
+++ b/ablescript/src/ast.rs
@@ -50,6 +50,39 @@ pub enum AssignableKind {
     Index { indices: Vec<Expr> },
 }
 
+impl Assignable {
+    pub fn from_expr(expr: Expr) -> Result<Assignable, ()> {
+        match expr.kind {
+            ExprKind::Variable(ident) => Ok(Assignable {
+                ident: Ident::new(ident, expr.span),
+                kind: AssignableKind::Variable,
+            }),
+            ExprKind::Index { expr, index } => Self::from_index(*expr, *index),
+            _ => Err(()),
+        }
+    }
+
+    fn from_index(mut buf: Expr, index: Expr) -> Result<Assignable, ()> {
+        let mut indices = vec![index];
+        let ident = loop {
+            match buf.kind {
+                ExprKind::Variable(ident) => break ident,
+                ExprKind::Index { expr, index } => {
+                    indices.push(*index);
+                    buf = *expr;
+                }
+                _ => return Err(()),
+            }
+        };
+
+        indices.reverse();
+        Ok(Assignable {
+            ident: Ident::new(ident, buf.span),
+            kind: AssignableKind::Index { indices },
+        })
+    }
+}
+
 #[derive(Debug, PartialEq, Clone, Hash)]
 pub struct Block {
     pub block: Vec<Stmt>,
diff --git a/ablescript/src/parser.rs b/ablescript/src/parser.rs
index d850f60..1aa4876 100644
--- a/ablescript/src/parser.rs
+++ b/ablescript/src/parser.rs
@@ -355,16 +355,7 @@ impl<'source> Parser<'source> {
 
                 // Variable Assignment
                 Token::Equal => {
-                    let assignable = buf.take().and_then(|buf| match buf.kind {
-                        ExprKind::Variable(ident) => Some(Assignable {
-                            ident: Ident::new(ident, buf.span),
-                            kind: AssignableKind::Variable,
-                        }),
-                        ExprKind::Index { expr, index } => self.cart_assignable_flow(*expr, *index),
-                        _ => None,
-                    });
-
-                    if let Some(assignable) = assignable {
+                    if let Some(Ok(assignable)) = buf.take().map(Assignable::from_expr) {
                         break StmtKind::Assign {
                             assignable,
                             value: self.expr_flow(Token::Semicolon)?,
@@ -395,27 +386,6 @@ impl<'source> Parser<'source> {
         Ok(r)
     }
 
-    /// Parse Cart Assignable flow
-    fn cart_assignable_flow(&mut self, mut buf: Expr, index: Expr) -> Option<Assignable> {
-        let mut indices = vec![index];
-        let ident = loop {
-            match buf.kind {
-                ExprKind::Variable(ident) => break ident,
-                ExprKind::Index { expr, index } => {
-                    indices.push(*index);
-                    buf = *expr;
-                }
-                _ => return None,
-            }
-        };
-
-        indices.reverse();
-        Some(Assignable {
-            ident: Ident::new(ident, buf.span),
-            kind: AssignableKind::Index { indices },
-        })
-    }
-
     /// Parse If flow
     ///
     /// Consists of condition and block, there is no else

From 48d9d1e2e16da1a7c28584cf0b83f022dd196bb5 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Sat, 23 Oct 2021 21:53:21 +0200
Subject: [PATCH 29/37] Read in AST takes Assignable instead of Ident

---
 ablescript/src/ast.rs       |  2 +-
 ablescript/src/interpret.rs | 11 +++++++++--
 ablescript/src/parser.rs    | 14 ++++++++------
 3 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/ablescript/src/ast.rs b/ablescript/src/ast.rs
index fa30420..a5f1905 100644
--- a/ablescript/src/ast.rs
+++ b/ablescript/src/ast.rs
@@ -144,7 +144,7 @@ pub enum StmtKind {
         args: Vec<Expr>,
     },
     Print(Expr),
-    Read(Ident),
+    Read(Assignable),
     Melo(Ident),
     Rlyeh,
     Rickroll,
diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index 1c7f096..356e9f3 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -280,14 +280,21 @@ impl ExecEnv {
                     .write_all(include_str!("rickroll").as_bytes())
                     .expect("Failed to write to stdout");
             }
-            StmtKind::Read(ident) => {
+            StmtKind::Read(assignable) => {
                 let mut value = 0;
                 for _ in 0..READ_BITS {
                     value <<= 1;
                     value += self.get_bit()? as i32;
                 }
 
-                self.get_var_mut(ident)?.value.replace(Value::Int(value));
+                match assignable.kind {
+                    AssignableKind::Variable => {
+                        self.get_var_mut(&assignable.ident)?
+                            .value
+                            .replace(Value::Int(value));
+                    }
+                    AssignableKind::Index { .. } => todo!(),
+                }
             }
         }
 
diff --git a/ablescript/src/parser.rs b/ablescript/src/parser.rs
index 1aa4876..a397287 100644
--- a/ablescript/src/parser.rs
+++ b/ablescript/src/parser.rs
@@ -370,12 +370,14 @@ impl<'source> Parser<'source> {
 
                 // Read input
                 Token::Read => {
-                    if let Some(Expr {
-                        kind: ExprKind::Variable(ident),
-                        span,
-                    }) = buf
-                    {
-                        break self.semi_terminated(StmtKind::Read(Ident::new(ident, span)))?;
+                    if let Some(Ok(assignable)) = buf.take().map(Assignable::from_expr) {
+                        self.require(Token::Semicolon)?;
+                        break StmtKind::Read(assignable);
+                    } else {
+                        return Err(Error::new(
+                            ErrorKind::UnexpectedToken(Token::Read),
+                            self.lexer.span(),
+                        ));
                     }
                 }
 

From 7e0daeab29443234f96e398e8987ca1c5a8945cf Mon Sep 17 00:00:00 2001
From: Alex Bethel <abethel@cs.nmt.edu>
Date: Sat, 23 Oct 2021 14:17:17 -0600
Subject: [PATCH 30/37] Almost get cart assignments working

---
 ablescript/src/interpret.rs | 9 ++++++++-
 1 file changed, 8 insertions(+), 1 deletion(-)

diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index 356e9f3..3bd8c78 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -254,8 +254,15 @@ impl ExecEnv {
                         let mut cell = self.get_var_rc(&assignable.ident)?;
                         for index in indices {
                             let index = self.eval_expr(index)?;
+
                             let value = cell.borrow().to_owned();
-                            cell = Rc::clone(value.into_cart().get(&index).unwrap());
+                            let mut value = value.into_cart();
+                            if let Some(x) = value.get(&index) {
+                                cell = Rc::clone(x);
+                            } else {
+                                cell = Rc::new(RefCell::new(Value::Cart(Default::default())));
+                                value.insert(index, Rc::clone(&cell));
+                            }
                         }
                         cell.replace(value);
                     }

From 2871e95e75c572741a4f93d891947774d391e117 Mon Sep 17 00:00:00 2001
From: Alex Bethel <abethel@cs.nmt.edu>
Date: Sat, 23 Oct 2021 15:08:10 -0600
Subject: [PATCH 31/37] Get cart assignments working

---
 ablescript/src/interpret.rs | 20 +++++++++++++-------
 1 file changed, 13 insertions(+), 7 deletions(-)

diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index 3bd8c78..d7db46b 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -255,14 +255,20 @@ impl ExecEnv {
                         for index in indices {
                             let index = self.eval_expr(index)?;
 
-                            let value = cell.borrow().to_owned();
-                            let mut value = value.into_cart();
-                            if let Some(x) = value.get(&index) {
-                                cell = Rc::clone(x);
-                            } else {
-                                cell = Rc::new(RefCell::new(Value::Cart(Default::default())));
-                                value.insert(index, Rc::clone(&cell));
+                            let next_cell;
+                            match &mut *cell.borrow_mut() {
+                                Value::Cart(c) => {
+                                    if let Some(x) = c.get(&index) {
+                                        next_cell = Rc::clone(x);
+                                    } else {
+                                        next_cell =
+                                            Rc::new(RefCell::new(Value::Cart(Default::default())));
+                                        c.insert(index, Rc::clone(&next_cell));
+                                    }
+                                }
+                                _ => todo!(),
                             }
+                            cell = next_cell;
                         }
                         cell.replace(value);
                     }

From 9712d58962e182773cc1ab14aae8cca426fed122 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Sat, 23 Oct 2021 23:20:45 +0200
Subject: [PATCH 32/37] Renamed `semi_terminated` to `semicolon_terminated`

---
 ablescript/src/parser.rs | 14 +++++++-------
 1 file changed, 7 insertions(+), 7 deletions(-)

diff --git a/ablescript/src/parser.rs b/ablescript/src/parser.rs
index a397287..4f8bf23 100644
--- a/ablescript/src/parser.rs
+++ b/ablescript/src/parser.rs
@@ -76,19 +76,19 @@ impl<'source> Parser<'source> {
             Token::Melo => Ok(Stmt::new(self.melo_flow()?, start..self.lexer.span().end)),
             Token::Loop => Ok(Stmt::new(self.loop_flow()?, start..self.lexer.span().end)),
             Token::Break => Ok(Stmt::new(
-                self.semi_terminated(StmtKind::Break)?,
+                self.semicolon_terminated(StmtKind::Break)?,
                 start..self.lexer.span().end,
             )),
             Token::HopBack => Ok(Stmt::new(
-                self.semi_terminated(StmtKind::HopBack)?,
+                self.semicolon_terminated(StmtKind::HopBack)?,
                 start..self.lexer.span().end,
             )),
             Token::Rlyeh => Ok(Stmt::new(
-                self.semi_terminated(StmtKind::Rlyeh)?,
+                self.semicolon_terminated(StmtKind::Rlyeh)?,
                 start..self.lexer.span().end,
             )),
             Token::Rickroll => Ok(Stmt::new(
-                self.semi_terminated(StmtKind::Rickroll)?,
+                self.semicolon_terminated(StmtKind::Rickroll)?,
                 start..self.lexer.span().end,
             )),
 
@@ -116,7 +116,7 @@ impl<'source> Parser<'source> {
     /// Require statement to be semicolon terminated
     ///
     /// Utility function for short statements
-    fn semi_terminated(&mut self, stmt_kind: StmtKind) -> Result<StmtKind, Error> {
+    fn semicolon_terminated(&mut self, stmt_kind: StmtKind) -> Result<StmtKind, Error> {
         self.require(Token::Semicolon)?;
         Ok(stmt_kind)
     }
@@ -340,7 +340,7 @@ impl<'source> Parser<'source> {
                     let stmt = StmtKind::Print(buf.take().ok_or_else(|| {
                         Error::new(ErrorKind::UnexpectedToken(Token::Print), self.lexer.span())
                     })?);
-                    break self.semi_terminated(stmt)?;
+                    break self.semicolon_terminated(stmt)?;
                 }
 
                 // Functio call
@@ -533,7 +533,7 @@ impl<'source> Parser<'source> {
     /// Parse Melo flow
     fn melo_flow(&mut self) -> Result<StmtKind, Error> {
         let ident = self.get_ident()?;
-        self.semi_terminated(StmtKind::Melo(ident))
+        self.semicolon_terminated(StmtKind::Melo(ident))
     }
 
     /// Parse loop flow

From 99f84dfd5bc22a494f3ae4b5b47dee700d9609e6 Mon Sep 17 00:00:00 2001
From: Alex Bethel <abethel@cs.nmt.edu>
Date: Fri, 5 Nov 2021 16:18:07 -0600
Subject: [PATCH 33/37] Coerce indexing assignments into non-carts

---
 ablescript/src/interpret.rs | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index d7db46b..8ea0472 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -11,6 +11,7 @@ use std::{
     cell::RefCell,
     collections::{HashMap, VecDeque},
     io::{stdin, stdout, Read, Write},
+    mem::swap,
     ops::Range,
     process::exit,
     rc::Rc,
@@ -266,7 +267,18 @@ impl ExecEnv {
                                         c.insert(index, Rc::clone(&next_cell));
                                     }
                                 }
-                                _ => todo!(),
+                                x => {
+                                    // Annoying borrow checker dance
+                                    // to move *x.
+                                    let mut tmp = Value::Nul;
+                                    swap(&mut tmp, x);
+
+                                    let mut c = tmp.into_cart();
+                                    next_cell =
+                                        Rc::new(RefCell::new(Value::Cart(Default::default())));
+                                    c.insert(index, Rc::clone(&next_cell));
+                                    *x = Value::Cart(c);
+                                }
                             }
                             cell = next_cell;
                         }

From 8a04d9d1e06f28538c5334fa45c8344ec6607358 Mon Sep 17 00:00:00 2001
From: Alex Bethel <abethel@cs.nmt.edu>
Date: Fri, 5 Nov 2021 17:09:53 -0600
Subject: [PATCH 34/37] Assign read syntax

---
 ablescript/src/interpret.rs | 93 ++++++++++++++++++-------------------
 1 file changed, 45 insertions(+), 48 deletions(-)

diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index 8ea0472..e1c3af5 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -20,7 +20,7 @@ use std::{
 use rand::random;
 
 use crate::{
-    ast::{AssignableKind, Expr, ExprKind, Ident, Stmt, StmtKind},
+    ast::{Assignable, AssignableKind, Expr, ExprKind, Ident, Stmt, StmtKind},
     base_55,
     consts::ablescript_consts,
     error::{Error, ErrorKind},
@@ -246,45 +246,7 @@ impl ExecEnv {
                 }
             },
             StmtKind::Assign { assignable, value } => {
-                let value = self.eval_expr(value)?;
-                match assignable.kind {
-                    AssignableKind::Variable => {
-                        self.get_var_mut(&assignable.ident)?.value.replace(value);
-                    }
-                    AssignableKind::Index { ref indices } => {
-                        let mut cell = self.get_var_rc(&assignable.ident)?;
-                        for index in indices {
-                            let index = self.eval_expr(index)?;
-
-                            let next_cell;
-                            match &mut *cell.borrow_mut() {
-                                Value::Cart(c) => {
-                                    if let Some(x) = c.get(&index) {
-                                        next_cell = Rc::clone(x);
-                                    } else {
-                                        next_cell =
-                                            Rc::new(RefCell::new(Value::Cart(Default::default())));
-                                        c.insert(index, Rc::clone(&next_cell));
-                                    }
-                                }
-                                x => {
-                                    // Annoying borrow checker dance
-                                    // to move *x.
-                                    let mut tmp = Value::Nul;
-                                    swap(&mut tmp, x);
-
-                                    let mut c = tmp.into_cart();
-                                    next_cell =
-                                        Rc::new(RefCell::new(Value::Cart(Default::default())));
-                                    c.insert(index, Rc::clone(&next_cell));
-                                    *x = Value::Cart(c);
-                                }
-                            }
-                            cell = next_cell;
-                        }
-                        cell.replace(value);
-                    }
-                }
+                self.assign(assignable, self.eval_expr(value)?)?;
             }
             StmtKind::Break => {
                 return Ok(HaltStatus::Break(stmt.span.clone()));
@@ -312,20 +274,55 @@ impl ExecEnv {
                     value += self.get_bit()? as i32;
                 }
 
-                match assignable.kind {
-                    AssignableKind::Variable => {
-                        self.get_var_mut(&assignable.ident)?
-                            .value
-                            .replace(Value::Int(value));
-                    }
-                    AssignableKind::Index { .. } => todo!(),
-                }
+                self.assign(assignable, Value::Int(value))?;
             }
         }
 
         Ok(HaltStatus::Finished)
     }
 
+    /// Assign a value to an Assignable.
+    fn assign(&mut self, dest: &Assignable, value: Value) -> Result<(), Error> {
+        match dest.kind {
+            AssignableKind::Variable => {
+                self.get_var_mut(&dest.ident)?.value.replace(value);
+            }
+            AssignableKind::Index { ref indices } => {
+                let mut cell = self.get_var_rc(&dest.ident)?;
+                for index in indices {
+                    let index = self.eval_expr(index)?;
+
+                    let next_cell;
+                    match &mut *cell.borrow_mut() {
+                        Value::Cart(c) => {
+                            if let Some(x) = c.get(&index) {
+                                next_cell = Rc::clone(x);
+                            } else {
+                                next_cell = Rc::new(RefCell::new(Value::Cart(Default::default())));
+                                c.insert(index, Rc::clone(&next_cell));
+                            }
+                        }
+                        x => {
+                            // Annoying borrow checker dance
+                            // to move *x.
+                            let mut tmp = Value::Nul;
+                            swap(&mut tmp, x);
+
+                            let mut c = tmp.into_cart();
+                            next_cell = Rc::new(RefCell::new(Value::Cart(Default::default())));
+                            c.insert(index, Rc::clone(&next_cell));
+                            *x = Value::Cart(c);
+                        }
+                    }
+                    cell = next_cell;
+                }
+                cell.replace(value);
+            }
+        }
+
+        Ok(())
+    }
+
     /// Call a function with the given arguments (i.e., actual
     /// parameters). If the function invocation fails for some reason,
     /// report the error at `span`.

From 38a3414e8831536915aefd34355b69078491833c Mon Sep 17 00:00:00 2001
From: Alex Bethel <abethel@cs.nmt.edu>
Date: Sat, 27 Nov 2021 11:02:41 -0600
Subject: [PATCH 35/37] Slightly better ExecEnv::assign

A little more idiomatic, avoid some borrow checker clumsiness, add
comments.
---
 ablescript/src/interpret.rs | 37 ++++++++++++++++++++++---------------
 ablescript/src/variables.rs |  6 ++++++
 2 files changed, 28 insertions(+), 15 deletions(-)

diff --git a/ablescript/src/interpret.rs b/ablescript/src/interpret.rs
index e1c3af5..5c9cae6 100644
--- a/ablescript/src/interpret.rs
+++ b/ablescript/src/interpret.rs
@@ -11,7 +11,7 @@ use std::{
     cell::RefCell,
     collections::{HashMap, VecDeque},
     io::{stdin, stdout, Read, Write},
-    mem::swap,
+    mem::take,
     ops::Range,
     process::exit,
     rc::Rc,
@@ -292,28 +292,35 @@ impl ExecEnv {
                 for index in indices {
                     let index = self.eval_expr(index)?;
 
-                    let next_cell;
-                    match &mut *cell.borrow_mut() {
+                    let next_cell = match &mut *cell.borrow_mut() {
                         Value::Cart(c) => {
+                            // cell is a cart, so we can do simple
+                            // indexing.
                             if let Some(x) = c.get(&index) {
-                                next_cell = Rc::clone(x);
+                                // cell[index] exists, get a shared
+                                // reference to it.
+                                Rc::clone(x)
                             } else {
-                                next_cell = Rc::new(RefCell::new(Value::Cart(Default::default())));
+                                // cell[index] does not exist, so we
+                                // insert an empty cart by default
+                                // instead.
+                                let next_cell =
+                                    Rc::new(RefCell::new(Value::Cart(Default::default())));
                                 c.insert(index, Rc::clone(&next_cell));
+                                next_cell
                             }
                         }
                         x => {
-                            // Annoying borrow checker dance
-                            // to move *x.
-                            let mut tmp = Value::Nul;
-                            swap(&mut tmp, x);
-
-                            let mut c = tmp.into_cart();
-                            next_cell = Rc::new(RefCell::new(Value::Cart(Default::default())));
-                            c.insert(index, Rc::clone(&next_cell));
-                            *x = Value::Cart(c);
+                            // cell is not a cart; `take` it, convert
+                            // it into a cart, and write the result
+                            // back into it.
+                            let mut cart = take(x).into_cart();
+                            let next_cell = Rc::new(RefCell::new(Value::Cart(Default::default())));
+                            cart.insert(index, Rc::clone(&next_cell));
+                            *x = Value::Cart(cart);
+                            next_cell
                         }
-                    }
+                    };
                     cell = next_cell;
                 }
                 cell.replace(value);
diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index fb663a5..99f7955 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -60,6 +60,12 @@ pub enum Value {
     Cart(Cart),
 }
 
+impl Default for Value {
+    fn default() -> Self {
+        Self::Nul
+    }
+}
+
 impl Hash for Value {
     fn hash<H: std::hash::Hasher>(&self, state: &mut H) {
         discriminant(self).hash(state);

From 716e4997c5c0f906ff7be6971e10ebe6ed0de30e Mon Sep 17 00:00:00 2001
From: Alex Bethel <abethel@cs.nmt.edu>
Date: Sat, 27 Nov 2021 11:11:03 -0600
Subject: [PATCH 36/37] Avoid trailing comma in cart printout

---
 ablescript/src/variables.rs | 10 ++++++++--
 1 file changed, 8 insertions(+), 2 deletions(-)

diff --git a/ablescript/src/variables.rs b/ablescript/src/variables.rs
index 99f7955..5ee99cb 100644
--- a/ablescript/src/variables.rs
+++ b/ablescript/src/variables.rs
@@ -532,8 +532,14 @@ impl Display for Value {
                 let mut cart_vec = c.iter().collect::<Vec<_>>();
                 cart_vec.sort_by(|x, y| x.0.partial_cmp(y.0).unwrap_or(std::cmp::Ordering::Less));
 
-                for (key, value) in cart_vec {
-                    write!(f, "{} <= {}, ", value.borrow(), key)?;
+                for (idx, (key, value)) in cart_vec.into_iter().enumerate() {
+                    write!(
+                        f,
+                        "{}{} <= {}",
+                        if idx != 0 { ", " } else { "" },
+                        value.borrow(),
+                        key
+                    )?;
                 }
 
                 write!(f, "]")

From da1fcfd861139903d5154bc8eefa797c6e723e2c Mon Sep 17 00:00:00 2001
From: Alex Bethel <abethel@cs.nmt.edu>
Date: Sat, 27 Nov 2021 11:15:29 -0600
Subject: [PATCH 37/37] Fix unused code warnings

---
 ablescript/src/base_55.rs | 62 ---------------------------------------
 ablescript/src/brian.rs   |  3 ++
 2 files changed, 3 insertions(+), 62 deletions(-)

diff --git a/ablescript/src/base_55.rs b/ablescript/src/base_55.rs
index fa612eb..a822227 100644
--- a/ablescript/src/base_55.rs
+++ b/ablescript/src/base_55.rs
@@ -60,68 +60,6 @@ pub fn char2num(character: char) -> i32 {
         _ => 0,
     }
 }
-pub fn num2char(number: i32) -> char {
-    match number {
-        -26 => 'Z',
-        -25 => 'Y',
-        -24 => 'X',
-        -23 => 'W',
-        -22 => 'V',
-        -210 => 'U',
-        -20 => 'T',
-        -18 => 'R',
-        -19 => 'S',
-        -17 => 'Q',
-        -16 => 'P',
-        -15 => 'O',
-        -14 => 'N',
-        -13 => 'M',
-        -12 => 'L',
-        -11 => 'K',
-        -10 => 'J',
-        -9 => 'I',
-        -8 => 'H',
-        -7 => 'G',
-        -6 => 'F',
-        -5 => 'E',
-        -4 => 'D',
-        -3 => 'C',
-        -2 => 'B',
-        -1 => 'A',
-        0 => ' ',
-        1 => 'a',
-        2 => 'b',
-        3 => 'c',
-        4 => 'd',
-        5 => 'e',
-        6 => 'f',
-        7 => 'g',
-        8 => 'h',
-        9 => 'i',
-        10 => 'j',
-        11 => 'k',
-        12 => 'l',
-        13 => 'm',
-        14 => 'n',
-        15 => 'o',
-        16 => 'p',
-        17 => 'q',
-        18 => 'r',
-        19 => 's',
-        20 => 't',
-        21 => 'u',
-        22 => 'v',
-        23 => 'w',
-        24 => 'x',
-        25 => 'y',
-        26 => 'z',
-        //         NOTE(Able): Why does it jump to 53 here? MY REASONS ARE BEYOND YOUR UNDERSTANDING MORTAL
-        53 => '/',
-        54 => '\\',
-        55 => '.',
-        _ => ' ',
-    }
-}
 
 #[cfg(test)]
 mod tests {
diff --git a/ablescript/src/brian.rs b/ablescript/src/brian.rs
index 1a4bf12..630bdb9 100644
--- a/ablescript/src/brian.rs
+++ b/ablescript/src/brian.rs
@@ -18,6 +18,9 @@
 
 #![deny(missing_docs)]
 
+// Putting this here because we still don't use the entire capabilities of this module. ~~Alex
+#![allow(dead_code)]
+
 use std::{
     collections::VecDeque,
     error::Error,