finally allow bare returns

src/codegen_x86_64.rs

@@ -415,15 +415,18 @@ _builtin_environ:
                     .replace_range(prologue_offset..prologue_offset + patch.len(), &patch);
             }
             Stmt::Return { keyword: _, exprs } => {
-                if exprs.len() == 2 {
-                    self.compile_expr(env, &exprs[1])?;
-                    emit!(&mut self.output, "    push rax");
-                    self.compile_expr(env, &exprs[0])?;
-                    emit!(&mut self.output, "    pop rdx");
-                } else if exprs.len() == 1 {
-                    self.compile_expr(env, &exprs[0])?;
-                } else {
-                    todo!();
+                match exprs.len() {
+                    2 => {
+                        self.compile_expr(env, &exprs[1])?;
+                        emit!(&mut self.output, "    push rax");
+                        self.compile_expr(env, &exprs[0])?;
+                        emit!(&mut self.output, "    pop rdx");
+                    }
+                    1 => {
+                        self.compile_expr(env, &exprs[0])?;
+                    }
+                    0 => {}
+                    _ => todo!(),
                 }
                 emit!(&mut self.output, "    mov rsp, rbp");
                 emit!(&mut self.output, "    pop rbp");

src/parser.rs

@@ -327,10 +327,12 @@ impl Parser {
         } else if self.match_token(&[TokenType::KeywordReturn]) {
             let keyword = self.previous().clone();
             let mut exprs = vec![];
-            loop {
-                exprs.push(self.expression()?);
-                if !self.match_token(&[TokenType::Comma]) {
-                    break;
+            if !self.check(&TokenType::Dedent) {
+                loop {
+                    exprs.push(self.expression()?);
+                    if !self.match_token(&[TokenType::Comma]) {
+                        break;
+                    }
                 }
             }
             Ok(Stmt::Return { keyword, exprs })

src/std/std.zr

@@ -81,11 +81,11 @@ func mem.free[x: any] : void
 
 func ptr.free[x: ptr] : void
     if x == 0
-        return 0
+        return
 
     blk := (x - MEM_BLOCK_SIZE) as mem.Block
     if blk->free
-        return 0
+        return
 
     blk->free = true
 
@@ -733,7 +733,7 @@ func i64.to_str_buf[n: i64, buf: ptr] : void
     if n == 0
         buf[0] = '0'
         buf[1] = 0
-        return 0
+        return
 
     neg : bool = n < 0
     if neg
@@ -768,7 +768,7 @@ func i64.to_hex_str_buf[n: i64, buf: ptr] : void
     if n == 0
         buf[0] = '0'
         buf[1] = 0
-        return 0
+        return
 
     mask := (1 << 60) - 1
     tmp := _stackalloc(17)
@@ -849,7 +849,7 @@ func Array.new_preallocated_and_zeroed[size: i64] : Array
 
 func Array.nth[xs: Array, n: i64] : any
     if n < 0 || n >= xs->size
-        panic("array.nth out of bounds")
+        panic("Array.nth out of bounds")
     return mem.read64(xs->data + n * 8)
 
 func Array.set[xs: Array, n: i64, x: any] : void
@@ -882,14 +882,19 @@ func Array.free_with_items[xs: Array] : void
 
 func Array.pop[xs: Array] : any
     if xs->size == 0
-        panic("array.pop on empty array")
-    x : any = xs->nth(xs->size - 1)
+        panic("Array.pop on empty array")
+    x : any = Array.last(xs)
     xs->size = xs->size - 1
     return x
 
+func Array.last[xs: Array] : any
+    if xs->size == 0
+        panic("Array.last on empty array")
+    return xs->nth(xs->size - 1)
+
 func Array.slice[xs: Array, start: i64, length: i64] : Array
     if start < 0 || length < 0 || start + length > xs->size
-        panic("array.slice out of bounds")
+        panic("Array.slice out of bounds")
 
     new_array := Array.new_preallocated_and_zeroed(length)
     mem.copy(xs->data + start * 8, new_array->data, length * 8)
@@ -971,7 +976,7 @@ func HashMap.insert[map: HashMap, key: str, value: any] : void
     while current as ptr
         if current->key->equal(key)
             current->value = value
-            return 0
+            return
         current = current->next
 
     new_node := new* HashMap._Node
@@ -1005,7 +1010,7 @@ func HashMap.delete[map: HashMap, key: str] : void
             
             current->key->free()
             mem.free(current)
-            return 0
+            return
 
         prev = current
         current = current->next

src/typechecker.rs

@@ -329,17 +329,16 @@ impl<'a> TypeChecker<'a> {
                 env.pop_scope();
             }
             Stmt::Return { keyword, exprs } => {
-                let expected = if self.current_function_return_type == "void" {
-                    "i64".into()
+                let joined_type = if exprs.is_empty() {
+                    "void".into()
                 } else {
-                    self.current_function_return_type.clone()
+                    exprs
+                        .iter()
+                        .map(|e| self.typecheck_expr(env, e))
+                        .collect::<Result<Vec<String>, _>>()?
+                        .join(",")
                 };
-                let joined_type = exprs
-                    .iter()
-                    .map(|e| self.typecheck_expr(env, e))
-                    .collect::<Result<Vec<String>, _>>()?
-                    .join(",");
-                expect_type!(joined_type, expected, keyword.loc);
+                expect_type!(joined_type, self.current_function_return_type, keyword.loc);
             }
             Stmt::Break => {}
             Stmt::Continue => {}