parser: make println consume parens

examples/hello.v

@@ -1,12 +1,13 @@
-//const (
-//	Cock = 1
-//	Ball = 2
-//	Deals = 3
-//	Businesses = 4
-//)
+const (
+	Cock = 1
+	Ball = 2 + 3
+	Deals = 3
+	Businesses = 4
+)
 
 fn main(a int) int {
 	1 + 2 + 3 + 4
 	1 + 1 * 1
 	3 / (51 + 2)
+	println(2 * 1956)
 }

src/parser.zig

@@ -91,10 +91,12 @@ pub const Parser = struct {
     }
 
     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("consumed {}, now has {}\n", ttype, self.peek());
+            std.debug.warn(" now has {}\n", self.peek());
             return cur;
         }
 
@@ -379,6 +381,7 @@ pub const Parser = struct {
         _ = try self.consumeSingle(.LeftBrace);
 
         while (self.peek().ttype != .RightBrace) {
+            std.debug.warn("get smt with cur {}\n", self.peek().ttype);
             var node = try self.parseStmt();
             ast.printNode(node, 0);
             try stmts.append(node.Stmt);
@@ -402,7 +405,11 @@ pub const Parser = struct {
 
     fn parsePrintln(self: *@This()) !*Stmt {
         _ = try self.consumeSingle(.Println);
+
+        _ = try self.consumeSingle(.LeftParen);
         var expr = try self.parseExpr();
+        _ = try self.consumeSingle(.RightParen);
+
         return try Stmt.mkPrintln(self.allocator, expr.Expr);
     }
 
@@ -509,7 +516,10 @@ pub const Parser = struct {
                 _ = try self.nextToken();
                 var expr = (try self.parseExpr()).Expr;
                 _ = try self.consume(.RightParen, "Expected ')' after expression");
-                break :blk try self.mkGrouping(expr);
+
+                // for groupings, we don't want to skip tokens as we already
+                // consumed RightParen.
+                return try self.mkGrouping(expr);
             },
 
             else => blk: {