Deferreds Feature Request

[alan.spacer@…]

Wherein a features for jQuery's Deferred objects are proposed:

When you want to take an action for when ALL Deferred objects are resolved or rejected (ie. not unresolved), you have to wrap a secondary Deferred object around each of them, and ensure that these secondary Deferreds are always resolved. This is because in the multiple Deferreds case where one of the Deferreds is rejected, ""jQuery.when"" IMMEDIATELY FIRES the fail callbacks for its master Deferred, even if some of the Deferreds may still be unresolved at that point.

See:  http://stackoverflow.com/questions/5824615/

[john]

Nominating ticket for 1.7 discussion.

[rwaldron]

+0,

[jaubourg]

-1, Start with a plugin, I'll gladly incorporate this in ajaxHooks (which I'd like to have some deferred helpers too)

[timmywil]

+0, I like the idea.

[dmethvin]

-1, Plugin first?

[john]

+0

[ajpiano]

+1, I kind of think it's a bug that they don't work this way already.

[danheberden]

-1, For fear of deferreds turning into a feature creep pit of despair, use the building blocks to make a plugin

[rwaldron]

Plugin first

[rg1693@…]

Hello, I stumbled upon the same problem. I've written a modified version of $.when to fix it. (it can be tested at  http://jsfiddle.net/LTsLJ/ ):

var // Static reference to slice
        sliceDeferred = [].slice;
    $.notBrokenWhen = function( firstParam ) {
        var args = sliceDeferred.call( arguments, 0 ),
            i = 0,
            length = args.length,
            pValues = new Array( length ),
            count = length,
            pCount = length,
            deferred = length <= 1 && firstParam && jQuery.isFunction( firstParam.promise ) ?
                firstParam :
                jQuery.Deferred(),
            promise = deferred.promise(),
            rejectedFlag;
        function checkAll() {
            if (rejectedFlag) {
                deferred.rejectWith( deferred, args );            
            } else {
                deferred.resolveWith( deferred, args );
            }
        }
        function resolveFunc( i ) {
            return function( value ) {
                args[ i ] = arguments.length > 1 ? sliceDeferred.call( arguments, 0 ) : value;
                if ( !( --count ) ) {
                    checkAll();
                }
            };
        }
        function progressFunc( i ) {
            return function( value ) {
                pValues[ i ] = arguments.length > 1 ? sliceDeferred.call( arguments, 0 ) : value;
                deferred.notifyWith( promise, pValues );
            };
        }
        function rejectFunc( i ) {
            return function( value ) {
                rejectedFlag = true;
                args[ i ] = arguments.length > 1 ? sliceDeferred.call( arguments, 0 ) : value;
                if ( !( --count ) ) {
                    checkAll();
                }
            }
        }
        if ( length > 1 ) {
            for ( ; i < length; i++ ) {
                if ( args[ i ] && args[ i ].promise && jQuery.isFunction( args[ i ].promise ) ) {
                    args[ i ].promise().then( resolveFunc(i), rejectFunc(i), progressFunc(i) );
                } else {
                    --count;
                }
            }
            if ( !count ) {
                deferred.resolveWith( deferred, args );
            }
        } else if ( deferred !== firstParam ) {
            deferred.resolveWith( deferred, length ? [ firstParam ] : [] );
        }
        return promise;
    }

[rg1693@…]

And I also made a github project:  https://github.com/BiAiB/jquery-fullwhen