4 files changed, 29 insertions, 10 deletions

diff --git a/src/Node.zig b/src/Node.zig
index a5aa0d0..32e0643 100644
--- a/src/Node.zig
+++ b/src/Node.zig
@@ -4,6 +4,7 @@ const Token = @import("Token.zig");
 
 const Self = @This();
 
+allocator: std.mem.Allocator,
 left: ?*Self = null,
 right: ?*Self = null,
 tag: Tag,
@@ -11,25 +12,31 @@ token: Token,
 
 const Tag = enum {
     fndef,
+    fnsign,
+    type,
     number,
     add,
     sub,
 };
 
-pub const stub = Self{ .tag = undefined, .token = undefined };
+pub const stub = Self{
+    .allocator = undefined,
+    .tag = undefined,
+    .token = undefined,
+};
 
 pub fn init(allocator: std.mem.Allocator, tag: Tag, token: Token) !*Self {
     const self = try allocator.create(Self);
-    self.* = .{ .tag = tag, .token = token };
+    self.* = .{ .allocator = allocator, .tag = tag, .token = token };
     return self;
 }
 
-pub fn deinit(self: *Self, allocator: std.mem.Allocator) void {
+pub fn deinit(self: *Self) void {
     if (self.left != null)
-        self.left.?.deinit(allocator);
+        self.left.?.deinit();
     if (self.right != null)
-        self.right.?.deinit(allocator);
-    allocator.destroy(self);
+        self.right.?.deinit();
+    self.allocator.destroy(self);
 }
 
 pub fn chainLeft(self: *Self, left: *Self) *Self {
diff --git a/src/Parser.zig b/src/Parser.zig
index 43741e3..0062781 100644
--- a/src/Parser.zig
+++ b/src/Parser.zig
@@ -36,6 +36,11 @@ pub fn expect(self: *Self, tag: Token.Tag) !void {
     try (try self.lexer.peek()).expect(tag);
 }
 
+fn @"type"(self: *Self) !*Node {
+    try self.expect(.word);
+    return try Node.init(self.allocator, .type, try self.lexer.pop());
+}
+
 fn expr(self: *Self) !*Node {
     try self.expect(.number);
     return try Node.init(self.allocator, .number, try self.lexer.pop());
@@ -46,13 +51,20 @@ fn function(self: *Self) !*Node {
 
     try self.expect(.word);
     const node = try Node.init(self.allocator, .fndef, try self.lexer.pop());
-    errdefer node.deinit(self.allocator);
+    errdefer node.deinit();
+
+    const sign = try Node.init(self.allocator, .fnsign, try self.lexer.peek());
+    errdefer sign.deinit();
+    node.left = sign;
 
     try self.skip("(");
-    node.left = null;
+    sign.left = null;
     try self.skip(")");
 
+    sign.right = try self.type();
+
     node.right = try self.expr();
+    errdefer node.right.?.deinit();
     try self.skip(";");
     return node;
 }
diff --git a/src/main.zig b/src/main.zig
index 88054bb..94480c9 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -33,7 +33,7 @@ pub fn main() !void {
     var parser = Parser.init(arena.allocator(), &lexer);
     defer parser.deinit();
     if (try parser.parse()) |ast| {
-        defer ast.deinit(arena.allocator());
+        defer ast.deinit();
         std.log.debug("{}", .{ast.*});
     } else return Error.EmptyAST;
 }
diff --git a/test.o7 b/test.o7
index 6c06e3c..a7ea242 100644
--- a/test.o7
+++ b/test.o7
@@ -1 +1 @@
-fn main() 0;
+fn main() i32 0;