Skip to content


Subversion checkout URL

You can clone with
Download ZIP


IE Leak: Array.flatten #2175

ibolmo opened this Issue · 0 comments

1 participant


As per: #2127 (comment)

It appears that the calling of instanceof on 'non-objects' (mootools.js flatten()) causes the memory leaks in IE.

We ended up implementing the following:

if( {
        instanceOf = this.instanceOf = function(item, object) {
            if (item == null) return false;
            // Avoid calling instanceof on certain "non-objects" to prevent memory leaks in IE
            if (!item.hasOwnProperty) return false;
            var constructor = item.$constructor || item.constructor;
            while (constructor){
                if (constructor === object) return true;
                constructor = constructor.parent;
            return item instanceof object;
@ibolmo ibolmo closed this
@ibolmo ibolmo reopened this
@ibolmo ibolmo referenced this issue from a commit
Commit has since been removed from the repository and is no longer available.
@ibolmo ibolmo referenced this issue

Fixes #2175 #2264

@ibolmo ibolmo referenced this issue from a commit in ibolmo/mootools-core
@ibolmo ibolmo Fixes #2175
This adds an additional check to `instanceOf` that prevents extraneous
instanceof checks for non-objects (e.g. window) as per:

PASSES: IE6-9; FFx 3-5, 8, 10; Chrome latest; Safari 5; Opera 11
@ibolmo ibolmo closed this in 5223508
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Something went wrong with that request. Please try again.