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/*
Copyright (c) 2004-2006, The Dojo Foundation
All Rights Reserved.
Licensed under the Academic Free License version 2.1 or above OR the
modified BSD license. For more information on Dojo licensing, see:
http://dojotoolkit.org/community/licensing.shtml
*/
dojo.provide("dojo.Deferred");
dojo.require("dojo.lang.func");
dojo.Deferred = function (canceller) {
this.chain = [];
this.id = this._nextId();
this.fired = -1;
this.paused = 0;
this.results = [null, null];
this.canceller = canceller;
this.silentlyCancelled = false;
};
dojo.lang.extend(dojo.Deferred, {getFunctionFromArgs:function () {
var a = arguments;
if ((a[0]) && (!a[1])) {
if (dojo.lang.isFunction(a[0])) {
return a[0];
} else {
if (dojo.lang.isString(a[0])) {
return dj_global[a[0]];
}
}
} else {
if ((a[0]) && (a[1])) {
return dojo.lang.hitch(a[0], a[1]);
}
}
return null;
}, makeCalled:function () {
var deferred = new dojo.Deferred();
deferred.callback();
return deferred;
}, repr:function () {
var state;
if (this.fired == -1) {
state = "unfired";
} else {
if (this.fired == 0) {
state = "success";
} else {
state = "error";
}
}
return "Deferred(" + this.id + ", " + state + ")";
}, toString:dojo.lang.forward("repr"), _nextId:(function () {
var n = 1;
return function () {
return n++;
};
})(), cancel:function () {
if (this.fired == -1) {
if (this.canceller) {
this.canceller(this);
} else {
this.silentlyCancelled = true;
}
if (this.fired == -1) {
this.errback(new Error(this.repr()));
}
} else {
if ((this.fired == 0) && (this.results[0] instanceof dojo.Deferred)) {
this.results[0].cancel();
}
}
}, _pause:function () {
this.paused++;
}, _unpause:function () {
this.paused--;
if ((this.paused == 0) && (this.fired >= 0)) {
this._fire();
}
}, _continue:function (res) {
this._resback(res);
this._unpause();
}, _resback:function (res) {
this.fired = ((res instanceof Error) ? 1 : 0);
this.results[this.fired] = res;
this._fire();
}, _check:function () {
if (this.fired != -1) {
if (!this.silentlyCancelled) {
dojo.raise("already called!");
}
this.silentlyCancelled = false;
return;
}
}, callback:function (res) {
this._check();
this._resback(res);
}, errback:function (res) {
this._check();
if (!(res instanceof Error)) {
res = new Error(res);
}
this._resback(res);
}, addBoth:function (cb, cbfn) {
var enclosed = this.getFunctionFromArgs(cb, cbfn);
if (arguments.length > 2) {
enclosed = dojo.lang.curryArguments(null, enclosed, arguments, 2);
}
return this.addCallbacks(enclosed, enclosed);
}, addCallback:function (cb, cbfn) {
var enclosed = this.getFunctionFromArgs(cb, cbfn);
if (arguments.length > 2) {
enclosed = dojo.lang.curryArguments(null, enclosed, arguments, 2);
}
return this.addCallbacks(enclosed, null);
}, addErrback:function (cb, cbfn) {
var enclosed = this.getFunctionFromArgs(cb, cbfn);
if (arguments.length > 2) {
enclosed = dojo.lang.curryArguments(null, enclosed, arguments, 2);
}
return this.addCallbacks(null, enclosed);
return this.addCallbacks(null, cbfn);
}, addCallbacks:function (cb, eb) {
this.chain.push([cb, eb]);
if (this.fired >= 0) {
this._fire();
}
return this;
}, _fire:function () {
var chain = this.chain;
var fired = this.fired;
var res = this.results[fired];
var self = this;
var cb = null;
while (chain.length > 0 && this.paused == 0) {
var pair = chain.shift();
var f = pair[fired];
if (f == null) {
continue;
}
try {
res = f(res);
fired = ((res instanceof Error) ? 1 : 0);
if (res instanceof dojo.Deferred) {
cb = function (res) {
self._continue(res);
};
this._pause();
}
}
catch (err) {
fired = 1;
res = err;
}
}
this.fired = fired;
this.results[fired] = res;
if ((cb) && (this.paused)) {
res.addBoth(cb);
}
}});