remove some debug calls

README.md

@@ -1,6 +1,6 @@
 # vig
 
-a [v] parser in zig
+a [v] parser in zig, also a shitpost taken too far
 
 [v]: https://vlang.io
 
@@ -9,20 +9,33 @@ for more epic adventures)
 
 ## why
 
-because i want to learn parsers and what best to do it with a language i'm
+ - because i want to learn parsers and what best to do it with a language i'm
 negatively charged towards
+ - theres an ast now it looks pretty
+ - i finally understand recursive descent parsers
 
 ## variations
 
  - `for` is split between `for` and `loop` because my fucking god i cant stand
-    having *four* different variations of `for`.
+    having *four* different variations of `for` to parse.
 
  - struct initialization is with `Struct.{}`, not `Struct{}`, to remove parsing
-    ambiguities
+    ambiguities (`if a {}` and `a{}`, v solves that with case, e.g structs Must
+    Be Properly Titled and i can't bother with that)
+
+## todo
+
+ - no `for` yet
+ - no methods yet (`fn (v Type) blah() blah {...}`)
+ - do we really want a type system
+ - do we really want to output c
+ - do we really want to output llvm
+ - do we really want to output x86
 
 ## how
 
-```
+ - step 1: dab
+ - step 2: ```
 git clone https://gitdab.com/luna/vig.git
 cd vig
 zig build install --prefix ~/.local/

examples/hello.v

@@ -37,7 +37,7 @@ fn main(a int) int {
 		println('skirts')
 	}
 
-	cock_and_ball_torture('cbt', 1, 2, 3)
+	test('asd', 1, 2, 3)
 
 	return 23
 
@@ -48,5 +48,7 @@ fn main(a int) int {
 
 	p.x = 69
 
-	println(egg.scramble(3).with(cheddar)) 
+	println(a.b(3).c(d)) 
+
+	v()()()
 }

src/ast.zig

@@ -14,7 +14,6 @@ pub const NodeType = enum {
     ConstDecl,
     Struct,
     Block,
-    Expr,
     Stmt,
 };
 
@@ -238,7 +237,6 @@ pub const Node = union(NodeType) {
 
     Block: StmtList,
 
-    Expr: *Expr,
     Stmt: *Stmt,
 
     pub fn mkRoot(allocator: *std.mem.Allocator) !*Node {

src/ast_printer.zig

@@ -70,12 +70,6 @@ pub fn printNode(node: *Node, ident: usize) void {
             }
         },
 
-        .Expr => |expr| {
-            printIdent(ident);
-            printExpr(expr);
-            std.debug.warn("\n");
-        },
-
         .Stmt => |stmt| {
             printIdent(ident);
             printStmt(ident, stmt);

src/parser.zig

@@ -88,6 +88,8 @@ pub const Parser = struct {
         return token;
     }
 
+    /// Consume the current token type, then walk to the next token.
+    /// Returns the consumed token.
     fn consume(self: *Parser, ttype: TokenType, comptime msg: []const u8) !Token {
         if (self.check(ttype)) {
             var tok = self.peek();
@@ -99,16 +101,15 @@ pub const Parser = struct {
         return Result.CompileError;
     }
 
+    /// Consume the current token. Gives default error messages
     fn consumeSingle(self: *Parser, ttype: TokenType) !Token {
-        std.debug.warn("consume {}..?", ttype);
-
         if (self.check(ttype)) {
             var cur = self.peek();
             _ = try self.nextToken();
-            std.debug.warn(" now has {}\n", self.peek());
             return cur;
         }
 
+        // TODO maybe this could be entirely comptime?
         var buf_main: [1000]u8 = undefined;
         var buf = try std.fmt.bufPrint(
             buf_main[0..],
@@ -116,11 +117,12 @@ pub const Parser = struct {
             ttype,
             self.peek().ttype,
         );
-        try self.tokenError(self.peek(), buf);
 
+        try self.tokenError(self.peek(), buf);
         return Result.CompileError;
     }
 
+    /// check() against multiple tokens
     fn compareAnyOf(self: *@This(), ttypes: []TokenType) bool {
         for (ttypes) |ttype| {
             if (self.check(ttype)) return true;
@@ -129,6 +131,8 @@ pub const Parser = struct {
         return false;
     }
 
+    // TODO maybe move helper functions to ast_helper.zig?
+
     fn mkFnDecl(
         self: *Parser,
         name: Token,
@@ -160,12 +164,6 @@ pub const Parser = struct {
         return node;
     }
 
-    fn mkExpr(self: *Parser, expr: *Expr) !*ast.Node {
-        var node = try self.allocator.create(Node);
-        node.* = Node{ .Expr = expr };
-        return node;
-    }
-
     fn mkStmt(self: *Parser, stmt: *Stmt) !*ast.Node {
         var node = try self.allocator.create(Node);
         node.* = Node{ .Stmt = stmt };
@@ -411,17 +409,20 @@ pub const Parser = struct {
         errdefer consts.deinit();
 
         _ = try self.consumeSingle(.Const);
-
         _ = try self.consumeSingle(.LeftParen);
 
         while (self.peek().ttype != .RightParen) {
             const const_name = try self.consumeSingle(.Identifier);
             _ = try self.consumeSingle(.Equal);
 
+            // const declarations dont have type, a future type system must
+            // check the output type of the expression and assign it to the
+            // const later on.
+
             var expr = try self.parseExpr();
             try consts.append(ast.SingleConst{
                 .name = const_name,
-                .expr = expr.Expr,
+                .expr = expr,
             });
         }
 
@@ -463,31 +464,27 @@ pub const Parser = struct {
             .Struct => try self.parseStructDecl(),
 
             else => |ttype| blk: {
-                self.doError("(basic) expected fn/const, got {}\n", ttype);
+                self.doError("expected Fn, Const, Struct, got {}\n", ttype);
                 return Result.CompileError;
             },
         };
     }
 
-    fn parseBlock(self: *@This()) !*Node {
-        var stmts = ast.StmtList.init(self.allocator);
+    fn parseBlockInternal(self: *@This(), comptime T: type) !T {
+        var stmts = T.init(self.allocator);
         errdefer stmts.deinit();
 
         _ = try self.consumeSingle(.LeftBrace);
 
         while (self.peek().ttype != .RightBrace) {
-            var stmt = try self.parseDecl();
+            var stmt = try self.parseStmt();
             printer.printNode(try self.mkStmt(stmt), 0);
             try stmts.append(stmt);
         }
 
         _ = try self.consumeSingle(.RightBrace);
 
-        return try self.mkBlock(stmts);
-    }
-
-    fn parseDecl(self: *@This()) !*Stmt {
-        return try self.parseStmt();
+        return stmts;
     }
 
     fn parseStmt(self: *@This()) anyerror!*Stmt {
@@ -496,33 +493,25 @@ pub const Parser = struct {
             .Loop => try self.parseLoop(),
             .Println => try self.parsePrintln(),
             .Return => try self.parseReturn(),
-
-            // TODO make newlines tokens and consume newline?
             else => try self.parseStmtExpr(),
         };
     }
 
-    /// Copy of parseBlock for blocks in statements
+    /// Parse a list of statements.
+    fn parseBlock(self: *@This()) !*Node {
+        var stmts = try self.parseBlockInternal(ast.StmtList);
+        return try self.mkBlock(stmts);
+    }
+
+    /// parse blocks inside statements
     fn parseStmtBlock(self: *@This()) !ast.Block {
-        var block = ast.Block.init(self.allocator);
-        errdefer block.deinit();
-
-        _ = try self.consumeSingle(.LeftBrace);
-
-        while (self.peek().ttype != .RightBrace) {
-            var stmt = try self.parseDecl();
-            printer.printNode(try self.mkStmt(stmt), 0);
-            try block.append(stmt);
-        }
-
-        _ = try self.consumeSingle(.RightBrace);
-
+        var block = try self.parseBlockInternal(ast.Block);
         return block;
     }
 
     fn parseIfStmt(self: *@This()) !*Stmt {
         _ = try self.consumeSingle(.If);
-        var condition = (try self.parseExpr()).Expr;
+        var condition = try self.parseExpr();
 
         const then_branch = try self.parseStmtBlock();
 
@@ -546,11 +535,11 @@ pub const Parser = struct {
         var expr: ?*Expr = null;
         var body: ast.Block = undefined;
 
-        // infinite loop
+        // 'loop {' = infinite loop
         if (self.check(.LeftBrace)) {
             body = try self.parseStmtBlock();
         } else {
-            expr = (try self.parseExpr()).Expr;
+            expr = try self.parseExpr();
             body = try self.parseStmtBlock();
         }
 
@@ -559,7 +548,7 @@ pub const Parser = struct {
 
     fn parseReturn(self: *@This()) !*Stmt {
         const tok = try self.consumeSingle(.Return);
-        const expr = (try self.parseExpr()).Expr;
+        const expr = try self.parseExpr();
         return try Stmt.mkReturn(self.allocator, tok, expr);
     }
 
@@ -567,24 +556,23 @@ pub const Parser = struct {
         _ = try self.consumeSingle(.Println);
 
         _ = try self.consumeSingle(.LeftParen);
-        var expr = (try self.parseExpr()).Expr;
+        var expr = try self.parseExpr();
         _ = try self.consumeSingle(.RightParen);
 
         return try Stmt.mkPrintln(self.allocator, expr);
     }
 
     fn parseStmtExpr(self: *@This()) !*Stmt {
-        var expr = (try self.parseExpr()).Expr;
+        var expr = try self.parseExpr();
         return try self.mkStmtExpr(expr);
     }
 
-    fn parseExpr(self: *@This()) anyerror!*Node {
-        var expr: *Expr = try self.parseAssignment();
-        return self.mkExpr(expr);
+    fn parseExpr(self: *@This()) anyerror!*Expr {
+        return try self.parseAssignment();
     }
 
     fn parseAssignment(self: *@This()) anyerror!*Expr {
-        // there can be two types coming out of this function:
+        // there can be two assignments coming out of this function:
         //  - a mutable/immutable variable declaration with :=
         //  - an assignment to a variable with =
 
@@ -592,53 +580,50 @@ pub const Parser = struct {
         // of this is an Expr, we wrap variable assignments in an Expr as well.
         var mutable: bool = false;
 
-        std.debug.warn("start assignment pass with cur={}\n", self.peek());
-
         if (self.check(.Mut)) {
             _ = try self.consumeSingle(.Mut);
             mutable = true;
         }
 
         var expr = try self.parseOr();
-        std.debug.warn("lvalue: {}, cur: {}\n", expr, self.peek());
-
-        var value: *Expr = undefined;
-
-        var op: Token = undefined;
 
         if (self.check(.ColonEqual) or self.check(.Equal)) {
-            op = self.peek();
-            _ = try self.nextToken();
-            value = try self.parseAssignment();
-
-            switch (expr.*) {
-                .Variable => {
-                    switch (op.ttype) {
-                        .ColonEqual => return try self.mkVarDecl(expr.Variable, value, mutable),
-                        .Equal => return try self.mkAssign(expr.Variable, value),
-                        else => unreachable,
-                    }
-                },
-
-                .Get => |get| {
-                    if (op.ttype == .ColonEqual) {
-                        self.doError("can not initialize struct field");
-                        return Result.CompileError;
-                    }
-
-                    return try self.mkSet(get.struc, get.name, value);
-                },
-
-                else => |expr_typ| {
-                    self.doError("Invalid assignment target {}", expr_typ);
-                    return Result.CompileError;
-                },
-            }
+            return try self.finishAssignment(expr, mutable);
         }
 
         return expr;
     }
 
+    fn finishAssignment(self: *@This(), expr: *Expr, mutable: bool) !*Expr {
+        var op = self.peek();
+        _ = try self.nextToken();
+        var value = try self.parseAssignment();
+
+        switch (expr.*) {
+            .Variable => {
+                switch (op.ttype) {
+                    .ColonEqual => return try self.mkVarDecl(expr.Variable, value, mutable),
+                    .Equal => return try self.mkAssign(expr.Variable, value),
+                    else => unreachable,
+                }
+            },
+
+            .Get => |get| {
+                if (op.ttype == .ColonEqual) {
+                    self.doError("can not initialize struct field");
+                    return Result.CompileError;
+                }
+
+                return try self.mkSet(get.struc, get.name, value);
+            },
+
+            else => |expr_typ| {
+                self.doError("Invalid assignment target {}", expr_typ);
+                return Result.CompileError;
+            },
+        }
+    }
+
     fn parseOr(self: *@This()) !*Expr {
         var expr = try self.parseAnd();
 
@@ -744,18 +729,14 @@ pub const Parser = struct {
         return expr;
     }
 
+    /// Parse either:
+    ///  - A function call
+    ///  - A struct initialization (Point.{...})
+    ///  - A struct Get expression (p.x)
     fn parseCall(self: *@This()) !*Expr {
-        // we parse a primary expression instead of consuming a .Identifier
-        // since parseCall is connected to the rest of the parser. doing
-        // identifiers would break the rest of the rules that want primaries.
-
-        // nothing stops us from ensuring expr is a Variable though ;)
         var expr = try self.parsePrimary();
 
         while (true) {
-            std.debug.warn("maybe fncall / struct: {}\n", self.peek().ttype);
-            printer.printExpr(expr);
-
             if (self.check(.LeftParen)) {
                 _ = try self.consumeSingle(.LeftParen);
                 expr = try self.finishCall(expr);
@@ -766,7 +747,11 @@ pub const Parser = struct {
                     _ = try self.consumeSingle(.LeftBrace);
                     expr = try self.finishStructVal(expr);
                 } else {
-                    var name = try self.consume(.Identifier, "Expect property name after '.'");
+                    var name = try self.consume(
+                        .Identifier,
+                        "Expect property name after '.'",
+                    );
+
                     expr = try self.mkGet(expr, name);
                 }
             } else {
@@ -784,18 +769,17 @@ pub const Parser = struct {
         if (!self.check(.RightParen)) {
 
             // emulating do-while really badly
-            var arg = (try self.parseExpr()).Expr;
+            var arg = try self.parseExpr();
             try args.append(arg);
 
             while (self.check(.Comma)) {
                 _ = try self.consumeSingle(.Comma);
 
-                arg = (try self.parseExpr()).Expr;
+                arg = try self.parseExpr();
                 try args.append(arg);
             }
         }
 
-        // TODO shouldnt consume() return the current token, not nextToken?
         var paren = try self.consume(.RightParen, "Expected ')' after arguments");
 
         return self.mkCall(callee, paren, args);
@@ -817,7 +801,7 @@ pub const Parser = struct {
             // TODO check .Comma for the quick initialization {val,val,val}
 
             _ = try self.consumeSingle(.Colon);
-            const field_value = (try self.parseExpr()).Expr;
+            const field_value = try self.parseExpr();
 
             try inits.append(ast.StructInit{
                 .field = field_name,
@@ -845,7 +829,7 @@ pub const Parser = struct {
 
             .LeftParen => blk: {
                 _ = try self.nextToken();
-                var expr = (try self.parseExpr()).Expr;
+                var expr = try self.parseExpr();
                 _ = try self.consume(.RightParen, "Expected ')' after expression");
 
                 // for groupings, we don't want to skip tokens as we already
@@ -860,7 +844,6 @@ pub const Parser = struct {
         };
 
         _ = try self.nextToken();
-
         return expr;
     }
 };