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@tenbits
Last active August 29, 2015 13:58
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Deferred
function Deferred(){}
(function(){
Deferred.prototype = {
_isAsync: true,
_done: null,
_fail: null,
_always: null,
_resolved: null,
_rejected: null,
defer: function(){
this._rejected = null;
this._resolved = null;
},
resolve: function() {
var done = this._done,
always = this._always
;
this._resolved = arguments;
dfr_clearListeners(this);
arr_callOnce(done, this, arguments);
arr_callOnce(always, this, [ this ]);
return this;
},
reject: function() {
var fail = this._fail,
always = this._always
;
this._rejected = arguments;
dfr_clearListeners(this);
arr_callOnce(fail, this, arguments);
arr_callOnce(always, this, [ this ]);
return this;
},
resolveDelegate: function(){
return fn_proxy(this.resolve, this);
},
rejectDelegate: function(){
return fn_proxy(this.reject, this);
},
then: function(onSuccess, onError){
return this.done(onSuccess).fail(onError);
},
done: function(callback) {
return dfr_bind(
this,
this._resolved,
this._done || (this._done = []),
callback
);
},
fail: function(callback) {
return dfr_bind(
this,
this._rejected,
this._fail || (this._fail = []),
callback
);
},
always: function(callback) {
return dfr_bind(
this,
this._rejected || this._resolved,
this._always || (this._always = []),
callback
);
},
};
// PRIVATE
function dfr_bind(dfr, arguments_, listeners, callback){
if (callback == null)
return dfr;
if ( arguments_ != null)
callback.apply(dfr, arguments_);
else
listeners.push(callback);
return dfr;
}
function dfr_clearListeners(dfr) {
dfr._done = null;
dfr._fail = null;
dfr._always = null;
}
function arr_callOnce(arr, ctx, args) {
if (arr == null)
return;
var imax = arr.length,
i = -1,
fn;
while ( ++i < imax ) {
fn = arr[i];
if (fn)
fn.apply(ctx, args);
}
arr.length = 0;
}
function fn_proxy(fn, ctx) {
return function() {
return fn.apply(ctx, arguments);
};
}
}());
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