From 6546aaa704ad0dfe693e1c06f98e00ef69bceb57 Mon Sep 17 00:00:00 2001
From: yimi <yimi>
Date: Mon, 18 Sep 2017 06:47:05 +0000
Subject: [PATCH] rewrite the constructor for `ast`

---
 lib/ast.js | 25 ++++++++++++++-----------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/lib/ast.js b/lib/ast.js
index 0918574d..d253b09a 100644
--- a/lib/ast.js
+++ b/lib/ast.js
@@ -47,25 +47,28 @@ function DEFNODE(type, props, methods, base) {
     if (arguments.length < 4) base = AST_Node;
     if (!props) props = [];
     else props = props.split(/\s+/);
-    var self_props = props;
-    if (base && base.PROPS)
-        props = props.concat(base.PROPS);
-    var code = "return function AST_" + type + "(props){ if (props) { ";
-    for (var i = props.length; --i >= 0;) {
-        code += "this." + props[i] + " = props." + props[i] + ";";
+    var ctor = function (props) {
+        if (props) {
+            var ctor = this.CTOR;
+            do {
+                var self_props = ctor.SELF_PROPS;
+                for (var i = self_props.length; i;) {
+                    var k = self_props[--i];
+                    this[k] = props[k];
+                }
+            } while (ctor = ctor.BASE)
+            if (this.initialize) {
+                this.initialize();
+            }
+        }
     }
     var proto = base && new base;
-    if (proto && proto.initialize || (methods && methods.initialize))
-        code += "this.initialize();";
-    code += "}}";
-    var ctor = new Function(code)();
     if (proto) {
         ctor.prototype = proto;
         ctor.BASE = base;
     }
     if (base) base.SUBCLASSES.push(ctor);
     ctor.prototype.CTOR = ctor;
-    ctor.PROPS = props || null;
     ctor.SELF_PROPS = self_props;
     ctor.SUBCLASSES = [];
     if (type) {