From 7ba140dd736f1da3ed0d13f01ccfcd69e8e6cea6 Mon Sep 17 00:00:00 2001
From: Luna <git@l4.pm>
Date: Fri, 23 Aug 2019 15:42:50 -0300
Subject: [PATCH 1/2] add better ast printing

---
 src/ast.zig    | 25 +++++++++++++++++++++++++
 src/parser.zig |  6 ++++++
 src/runner.zig |  5 ++---
 3 files changed, 33 insertions(+), 3 deletions(-)

diff --git a/src/ast.zig b/src/ast.zig
index 52f25a9..310ce44 100644
--- a/src/ast.zig
+++ b/src/ast.zig
@@ -43,3 +43,28 @@ pub fn mkRoot(allocator: *std.mem.Allocator) !*Node {
     node.* = Node{ .Root = NodeList.init(allocator) };
     return node;
 }
+
+fn print(ident: usize, comptime fmt: []const u8, args: ...) void {
+    var i: usize = 0;
+    while (i < ident) : (i += 1) {
+        std.debug.warn("\t");
+    }
+
+    std.debug.warn(fmt, args);
+}
+
+pub fn printNode(node: *Node, ident: usize) void {
+    switch (node.*) {
+        .FnDecl => |proto| {
+            print(ident, "FnDecl name='{}'\n", proto.func_name.lexeme);
+        },
+        .Root => {
+            for (node.Root.toSlice()) |child| {
+                printNode(child, ident + 1);
+            }
+        },
+        else => {
+            print(ident, "unknown node: {}\n", node);
+        },
+    }
+}
diff --git a/src/parser.zig b/src/parser.zig
index f07ebc3..9ee366d 100644
--- a/src/parser.zig
+++ b/src/parser.zig
@@ -233,6 +233,12 @@ pub const Parser = struct {
             .Fn => blk: {
                 _ = try self.consumeSingle(.Fn);
                 var name = try self.consumeSingle(.Identifier);
+                _ = try self.consumeSingle(.LeftParen);
+                // TODO paramlist
+                _ = try self.consumeSingle(.RightParen);
+                _ = try self.consumeSingle(.LeftBrace);
+                // TODO block
+                _ = try self.consumeSingle(.RightBrace);
                 std.debug.warn("!fn name: {}\n", name);
                 break :blk try self.mkFnDecl(
                     name,
diff --git a/src/runner.zig b/src/runner.zig
index e0f6493..34d81d0 100644
--- a/src/runner.zig
+++ b/src/runner.zig
@@ -48,9 +48,8 @@ pub const Runner = struct {
 
         var it = root.Root.iterator();
 
-        while (it.next()) |node| {
-            std.debug.warn("{}\n", node.*);
-        }
+        std.debug.warn("parse tree\n");
+        ast.printNode(root, 0);
 
         return Result.Ok;
     }

From 89e386d2d4cddcc6c07c92905d7238695f992b1a Mon Sep 17 00:00:00 2001
From: Luna <git@l4.pm>
Date: Fri, 23 Aug 2019 15:52:04 -0300
Subject: [PATCH 2/2] add basic param parsing

---
 examples/hello.v |  2 +-
 src/ast.zig      | 19 ++++++++++++++-----
 src/parser.zig   | 20 +++++++++++++++-----
 3 files changed, 30 insertions(+), 11 deletions(-)

diff --git a/examples/hello.v b/examples/hello.v
index f328e4d..a20f831 100644
--- a/examples/hello.v
+++ b/examples/hello.v
@@ -1 +1 @@
-fn main() {}
+fn main( a int) {}
diff --git a/src/ast.zig b/src/ast.zig
index 310ce44..5e20aa6 100644
--- a/src/ast.zig
+++ b/src/ast.zig
@@ -3,7 +3,7 @@ const tokens = @import("tokens.zig");
 const Token = tokens.Token;
 
 pub const NodeList = std.ArrayList(*Node);
-pub const ParamList = std.ArrayList(*ParamDecl);
+pub const ParamList = std.ArrayList(ParamDecl);
 
 // TODO convert FnCall to something like PrefixOp / InfixOp / SuffixOp
 pub const NodeType = enum {
@@ -14,10 +14,10 @@ pub const NodeType = enum {
 };
 
 pub const ParamDecl = struct {
-    param_name: Token,
+    name: Token,
 
     // TODO types
-    param_type: Token,
+    typ: Token,
 };
 
 pub const FnDecl = struct {
@@ -55,8 +55,17 @@ fn print(ident: usize, comptime fmt: []const u8, args: ...) void {
 
 pub fn printNode(node: *Node, ident: usize) void {
     switch (node.*) {
-        .FnDecl => |proto| {
-            print(ident, "FnDecl name='{}'\n", proto.func_name.lexeme);
+        .FnDecl => |decl| {
+            print(ident, "FnDecl name='{}'\n", decl.func_name.lexeme);
+
+            for (decl.params.toSlice()) |param| {
+                print(
+                    ident + 1,
+                    "param: '{}' {}\n",
+                    param.name.lexeme,
+                    param.typ.lexeme,
+                );
+            }
         },
         .Root => {
             for (node.Root.toSlice()) |child| {
diff --git a/src/parser.zig b/src/parser.zig
index 9ee366d..e45d404 100644
--- a/src/parser.zig
+++ b/src/parser.zig
@@ -231,19 +231,29 @@ pub const Parser = struct {
     fn topDecl(self: *@This()) !?*Node {
         return switch (self.peek().ttype) {
             .Fn => blk: {
+                var param_list = ast.ParamList.init(self.allocator);
+                errdefer param_list.deinit();
+
                 _ = try self.consumeSingle(.Fn);
                 var name = try self.consumeSingle(.Identifier);
+
                 _ = try self.consumeSingle(.LeftParen);
-                // TODO paramlist
+
+                while (self.peek().ttype != .RightParen) {
+                    const param_name = try self.consumeSingle(.Identifier);
+                    const param_type = try self.consumeSingle(.Identifier);
+
+                    try param_list.append(ast.ParamDecl{ .name = param_name, .typ = param_type });
+                }
+
                 _ = try self.consumeSingle(.RightParen);
+
                 _ = try self.consumeSingle(.LeftBrace);
                 // TODO block
                 _ = try self.consumeSingle(.RightBrace);
+
                 std.debug.warn("!fn name: {}\n", name);
-                break :blk try self.mkFnDecl(
-                    name,
-                    ast.ParamList.init(self.allocator),
-                );
+                break :blk try self.mkFnDecl(name, param_list);
             },
             else => |ttype| blk: {
                 self.doError("expected fn, got {}\n", ttype);