From 1846fe41aed5ef10755d2602188fc894db2244a9 Mon Sep 17 00:00:00 2001
From: Erin <erin@erindesu.cz>
Date: Tue, 12 Sep 2023 19:54:59 +0200
Subject: [PATCH] sth

---
 src/main.rs          |  1 +
 src/syntax/ast.rs    |  9 +++---
 src/syntax/parser.rs | 68 +++++++++++++++++++++++++++++++++-----------
 src/syntax/token.rs  |  2 +-
 4 files changed, 59 insertions(+), 21 deletions(-)

diff --git a/src/main.rs b/src/main.rs
index b4f78c5..da3537e 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -8,6 +8,7 @@ use utils::default;
 mod syntax;
 mod utils;
 
+
 fn main() -> Result<(), Box<dyn std::error::Error>> {
     let mut buf = default();
     stdin().read_to_string(&mut buf)?;
diff --git a/src/syntax/ast.rs b/src/syntax/ast.rs
index e351646..45fb1cf 100644
--- a/src/syntax/ast.rs
+++ b/src/syntax/ast.rs
@@ -36,6 +36,7 @@ pub enum Expr<'a> {
     Match(ExprRef<'a>, &'a [(Spanned<Pattern>, SpanExpr<'a>)]),
     Set(ExprRef<'a>, ExprRef<'a>),
     Func(Ident, &'a [Spanned<Pattern>], ExprRef<'a>),
+    Block(ExprList<'a>),
 }
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
@@ -57,7 +58,7 @@ pub enum BinaryOperator {
     Star,
     Slash,
     And,
-    Or,
+    VLine,
     Lt,
     Gt,
     Equ,
@@ -68,7 +69,7 @@ pub enum BinaryOperator {
 
 #[derive(Clone, Copy, Debug, PartialEq, Eq)]
 pub enum UnaryOperator {
-    Not,
-    Neg,
-    Deref,
+    Tilde,
+    Minus,
+    Star,
 }
diff --git a/src/syntax/parser.rs b/src/syntax/parser.rs
index 5266491..78b7b31 100644
--- a/src/syntax/parser.rs
+++ b/src/syntax/parser.rs
@@ -1,4 +1,4 @@
-use super::ast::{Literal, SpanExpr};
+use super::ast::{BinaryOperator, Literal, SpanExpr, UnaryOperator};
 
 use {
     super::{
@@ -15,39 +15,70 @@ use {
     logos::Lexer,
 };
 
+/// Equivalently-named unit variant mapping
+macro_rules! equivmap {
+    ($src:ident, $target:ident, [$variant0:ident $(, $variant:ident)* $(,)?] $(,)?) => {
+        just($src::$variant0).to($target::$variant0)
+            $(.or(just($src::$variant).to($target::$variant)))*
+    };
+}
+
 fn expr<'a, I>() -> impl Parser<'a, I, SpanExpr<'a>, Extra<'a>> + Clone
 where
     I: Input<'a, Token = Token, Span = SimpleSpan> + ValueInput<'a>,
 {
     recursive(|expr| {
         let ident = select!(Token::Ident(id) => Expr::Ident(id));
-        let atom = {
-            // Literal
-            select! {
-                Token::Int(a) => Literal::Integer(a),
-                Token::String(a) => Literal::String(a)
-            }
-            .map(Expr::Literal)
+
+        let literal = select! {
+            Token::Int(a) => Literal::Integer(a),
+            Token::String(a) => Literal::String(a)
         }
-        .or(ident)
-        .map_with_span(Spanned::new)
-        .or(expr
+        .map(Expr::Literal);
+
+        let atom = literal.or(ident).map_with_span(Spanned::new).or(expr
             .clone()
             .delimited_by(just(Token::LeftParen), just(Token::RightParen)));
 
         let call = atom
             .clone()
-            .pipe(arena_box)
-            .then(
+            .foldl_with_state(
                 expr.clone()
                     .separated_by(just(Token::Comma))
                     .allow_trailing()
                     .pipe(arena_collect)
-                    .delimited_by(just(Token::LeftParen), just(Token::RightParen)),
+                    .delimited_by(just(Token::LeftParen), just(Token::RightParen))
+                    .map_with_span(Spanned::new)
+                    .repeated(),
+                |expr, paramlist, state: &mut State| {
+                    Spanned::new(
+                        Expr::Call(state.arena.alloc(expr), paramlist.item),
+                        merge_spans(expr.span, paramlist.span),
+                    )
+                },
             )
-            .map(|(expr, params)| Expr::Call(expr, params));
+            .boxed();
 
-        call.map_with_span(Spanned::new).or(atom)
+        let unary = call;
+
+        let binary = unary.clone().foldl_with_state(
+            equivmap!(
+                Token,
+                BinaryOperator,
+                [Plus, Minus, Star, Slash, And, VLine, Lt, Gt, Equ, Nequ, LtEqu, GtEqu],
+            )
+            .map_with_span(Spanned::new)
+            .then(unary)
+            .repeated(),
+            |l, (op, r), state: &mut State| {
+                Spanned::new(
+                    Expr::Binary(op, state.arena.alloc(l), state.arena.alloc(r)),
+                    merge_spans(l.span, r.span),
+                )
+            },
+        );
+
+        binary.or(atom)
     })
 }
 
@@ -105,3 +136,8 @@ where
 {
     parser.map_with_state(|item, _, state| &*state.arena.alloc(item))
 }
+
+#[inline]
+fn merge_spans(start: SimpleSpan, end: SimpleSpan) -> SimpleSpan {
+    SimpleSpan::new(start.start, end.end)
+}
diff --git a/src/syntax/token.rs b/src/syntax/token.rs
index ecfc47a..6ce9a45 100644
--- a/src/syntax/token.rs
+++ b/src/syntax/token.rs
@@ -39,7 +39,7 @@ pub enum Token {
     #[token("*")] Star,
     #[token("/")] Slash,
     #[token("&")] And,
-    #[token("|")] Or,
+    #[token("|")] VLine,
     #[token("~")] Tilde,
     
     #[token("<")] Lt,