From 60ced2ccb6649526dd1e2bb6967b417503e903de Mon Sep 17 00:00:00 2001
From: Ivan De Marino <ivan.de.marino@gmail.com>
Date: Wed, 26 Sep 2012 01:13:38 +0100
Subject: [PATCH] Provide "detectType" inspired by D. Crockford

Addresses [Issue #800](http://code.google.com/p/phantomjs/issues/detail?id=800)
---
 src/bootstrap.js       | 19 +++++++++++++++++++
 src/modules/webpage.js | 16 ++++++++++++----
 2 files changed, 31 insertions(+), 4 deletions(-)

diff --git a/src/bootstrap.js b/src/bootstrap.js
index 9910a745..ca491857 100644
--- a/src/bootstrap.js
+++ b/src/bootstrap.js
@@ -291,3 +291,22 @@ phantom.onError = phantom.defaultErrorHandler;
 
 // Legacy way to use WebPage
 window.WebPage = require('webpage').create;
+
+// Remedy to fauly "typeof": "typeOf" by Douglas Crockford
+// NOTE: Renamed to "detectType" and added support for RegExp
+// @see http://javascript.crockford.com/remedial.html
+window.detectType = function (value) {
+    var s = typeof value;
+    if (s === 'object') {
+        if (value) {
+            if (value instanceof Array) {
+                s = 'array';
+            } else if (value instanceof RegExp) {
+                s = 'regexp';
+            }
+        } else {
+            s = 'null';
+        }
+    }
+    return s;
+};
diff --git a/src/modules/webpage.js b/src/modules/webpage.js
index 1fd8d8a9..082d00d4 100644
--- a/src/modules/webpage.js
+++ b/src/modules/webpage.js
@@ -238,17 +238,25 @@ function decorateNewPage(opts, page) {
      * @return  {*}                 the function call result
      */
     page.evaluate = function (func, args) {
-        var str, arg, i, l;
+        var str, arg, argType, i, l;
         if (!(func instanceof Function || typeof func === 'string' || func instanceof String)) {
             throw "Wrong use of WebPage#evaluate";
         }
         str = 'function() { return (' + func.toString() + ')(';
         for (i = 1, l = arguments.length; i < l; i++) {
             arg = arguments[i];
-            if (/object|string/.test(typeof arg) && !(arg instanceof RegExp)) {
-                str += 'JSON.parse(' + JSON.stringify(JSON.stringify(arg)) + '),';
-            } else {
+            argType = detectType(arg);
+
+            switch (argType) {
+            case "object": case "array":    //< for type "object" and "array"
+                str += "JSON.parse(" + JSON.stringify(JSON.stringify(arg)) + "),"
+                break;
+            case "string":                  //< for type "string"
+                str += '"' + arg +'",';
+                break;
+            default:                // for types: "null", "number", "function", "regexp", "undefined"
                 str += arg + ',';
+                break;
             }
         }
         str = str.replace(/,$/, '') + '); }';