fix function with lambda body

compiler/src/lib.rs

@@ -43,15 +43,15 @@ impl Compiler {
                     parser::BinaryOp::Sub => Instr::NumSub,
                     parser::BinaryOp::Mul => Instr::NumMul,
                     parser::BinaryOp::Div => Instr::NumDiv,
-                    // parser::BinaryOp::Eq => Instr::Eq,
-                    // parser::BinaryOp::Ne => Instr::Neq,
-                    // parser::BinaryOp::Lt => Instr::Lt,
-                    // parser::BinaryOp::Gt => Instr::Gt,
-                    // parser::BinaryOp::Le => Instr::Lte,
-                    // parser::BinaryOp::Ge => Instr::Gte,
+                    parser::BinaryOp::Eq => Instr::NumEq,
+                    parser::BinaryOp::Ne => todo!(),
+                    parser::BinaryOp::Lt => todo!(),
+                    parser::BinaryOp::Gt => todo!(),
+                    parser::BinaryOp::Le => todo!(),
+                    parser::BinaryOp::Ge => todo!(),
                     parser::BinaryOp::And => Instr::BoolAnd,
                     parser::BinaryOp::Or => Instr::BoolOr,
-                    _ => todo!(),
+                    parser::BinaryOp::Pipe => todo!(),
                 });
                 instrs
             }
@@ -128,10 +128,13 @@ impl Compiler {
         match stmt {
             Stmt::Fun(name, args, body) => {
                 let is_main = name == "main";
-                let mut instrs = vec![
-                    Instr::FuncMake(args, self.compile_expr(body.0)),
-                    Instr::Set(name),
-                ];
+                let mut instrs = match body.0 {
+                    // If the body is a lambda then we don't have to compile
+                    // it into a function
+                    Expr::Lambda(_, _) => self.compile_expr(body.0),
+                    _ => vec![Instr::FuncMake(args, self.compile_expr(body.0))],
+                };
+                instrs.push(Instr::Set(name));
                 if is_main {
                     instrs.pop();
                     instrs.push(Instr::FuncApply);

entry/src/main.rs

@@ -13,9 +13,12 @@ fn main() {
         if let Some(ast) = ast {
             let mut compiler = Compiler::new();
             let instrs = compiler.compile_program(ast);
-            instrs.iter().for_each(|i| println!("{:?}", i));
+            // instrs.iter().for_each(|i| println!("{:?}", i));
             let mut executor = Executor::new(instrs);
-            match executor.run() {
+            match executor.run_with(|exec| {
+                // println!("{:?}", exec.stack);
+                Ok(())
+            }) {
                 Ok(_) => {}
                 Err(e) => println!("Runtime error: {:?}", e),
             }

examples/sim.sial

@@ -1,4 +1,8 @@
+fun foo x = x
+
+fun fac n = if n == 0 then 1 else n * fac(n - 1)
+
 fun main = do
-    let foo = if true then 10 else 5 in
-        print(foo)
+    print(foo(1))
+    print(fac(5))
 end

vm/src/exec.rs

@@ -38,6 +38,15 @@ impl Executor {
         Ok(())
     }
 
+    pub fn run_with<F: Fn(&mut Self) -> Result<(), Error>>(&mut self, f: F) -> Result<(), Error> {
+        while self.ip < self.instrs.len() {
+            self.step()?;
+            self.ip += 1;
+            f(self)?;
+        }
+        Ok(())
+    }
+
     fn err(&self, msg: &str) -> Error {
         Error::make(msg, self.ip)
     }
@@ -93,10 +102,10 @@ impl Executor {
             .ok_or_else(|| self.err("invalid instruction pointer"))?;
 
         macro_rules! impl_num_binop {
-            ($op:tt) => {
+            ($op:tt, $ret:ident) => {
                 match (self.pop()?, self.pop()?) {
                     (Value::Num(a), Value::Num(b)) => {
-                        self.stack.push(Value::Num(a $op b));
+                        self.stack.push(Value::$ret(a $op b));
                     }
                     _ => return Err(Error::make("can't apply operator to non-numbers", self.ip)),
                 }
@@ -117,11 +126,12 @@ impl Executor {
             Instr::NumPush(x) => {
                 self.push(Value::Num(*x))?;
             }
-            Instr::NumAdd => impl_num_binop!(+),
-            Instr::NumSub => impl_num_binop!(-),
-            Instr::NumMul => impl_num_binop!(*),
-            Instr::NumDiv => impl_num_binop!(/),
-            Instr::NumMod => impl_num_binop!(%),
+            Instr::NumAdd => impl_num_binop!(+, Num),
+            Instr::NumSub => impl_num_binop!(-, Num),
+            Instr::NumMul => impl_num_binop!(*, Num),
+            Instr::NumDiv => impl_num_binop!(/, Num),
+            Instr::NumMod => impl_num_binop!(%, Num),
+            Instr::NumEq => impl_num_binop!(==, Bool),
 
             Instr::BoolPush(x) => {
                 self.push(Value::Bool(*x))?;

vm/src/model.rs

@@ -103,7 +103,8 @@ pub enum Instr {
     NumSub,       // │ 1 byte
     NumMul,       // │
     NumDiv,       // │
-    NumMod,       // ┘
+    NumMod,       // │
+    NumEq,        // ┘
 
     BoolPush(bool), // 2 bytes: 1 byte for the enum, 1 byte for the bool
     BoolAnd,        // ┐ 1 byte
@@ -171,7 +172,12 @@ impl Instr {
     pub fn size(&self) -> usize {
         match self {
             Instr::NumPush(_) => 1 + std::mem::size_of::<i64>(),
-            Instr::NumAdd | Instr::NumSub | Instr::NumMul | Instr::NumDiv | Instr::NumMod => 1,
+            Instr::NumAdd
+            | Instr::NumSub
+            | Instr::NumMul
+            | Instr::NumDiv
+            | Instr::NumMod
+            | Instr::NumEq => 1,
 
             Instr::BoolPush(_) => 1 + std::mem::size_of::<bool>(),
             Instr::BoolAnd | Instr::BoolOr | Instr::BoolNot => 1,
@@ -227,6 +233,7 @@ impl Instr {
             Instr::NumMul => bytes.push(index!()),
             Instr::NumDiv => bytes.push(index!()),
             Instr::NumMod => bytes.push(index!()),
+            Instr::NumEq => bytes.push(index!()),
 
             Instr::BoolPush(b) => {
                 bytes.push(index!());