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//>>built
// wrapped by build app
define("dojox/lang/async", ["dijit","dojo","dojox"], function(dijit,dojo,dojox){
dojo.provide("dojox.lang.async");
(function(){
var d = dojo, Deferred = d.Deferred, each = d.forEach, some = d.some,
async = dojox.lang.async, aps = Array.prototype.slice,
opts = Object.prototype.toString;
async.seq = function(x){
// summary:
// Executes functions sequentially. Waits if any of them returns Deferred.
var fs = opts.call(x) == "[object Array]" ? x : arguments;
return function(init){
var x = new Deferred();
each(fs, function(f){ x.addCallback(f); });
x.callback(init);
return x;
};
};
async.par = function(x){
// summary:
// Executes functions in parallel. Waits for all of them to finish.
var fs = opts.call(x) == "[object Array]" ? x : arguments;
return function(init){
var results = new Array(fs.length),
cancel = function(){
each(results, function(v){
if(v instanceof Deferred && v.fired < 0){
v.cancel();
}
});
},
x = new Deferred(cancel),
ready = fs.length;
each(fs, function(f, i){
var x;
try {
x = f(init);
}catch(e){
x = e;
}
results[i] = x;
});
var failed = some(results, function(v){
if(v instanceof Error){
cancel();
x.errback(v);
return true;
}
return false;
});
if(!failed){
each(results, function(v, i){
if(v instanceof Deferred){
v.addCallbacks(
function(v){
results[i] = v;
if(!--ready){
x.callback(results);
}
},
function(v){
cancel();
x.errback(v);
}
);
}else{
--ready;
}
});
}
if(!ready){
x.callback(results);
}
return x;
};
};
async.any = function(x){
// summary:
// Executes functions in parallel. As soon as one of them finishes
// cancels the rest.
var fs = opts.call(x) == "[object Array]" ? x : arguments;
return function(init){
var results = new Array(fs.length), noResult = true;
cancel = function(index){
each(results, function(v, i){
if(i != index && v instanceof Deferred && v.fired < 0){
v.cancel();
}
});
},
x = new Deferred(cancel);
each(fs, function(f, i){
var x;
try {
x = f(init);
}catch(e){
x = e;
}
results[i] = x;
});
var done = some(results, function(v, i){
if(!(v instanceof Deferred)){
cancel(i);
x.callback(v);
return true;
}
return false;
});
if(!done){
each(results, function(v, i){
v.addBoth(
function(v){
if(noResult){
noResult = false;
cancel(i);
x.callback(v);
}
}
);
});
}
return x;
};
};
async.select = function(cond, x){
// summary:
// Executes a condition, waits for it if necessary, and executes
// Nth function from list.
var fs = opts.call(x) == "[object Array]" ? x : aps.call(arguments, 1);
return function(init){
return new Deferred().addCallback(cond).addCallback(function(v){
if(typeof v == "number" && v >= 0 && v < fs.length){
return fs[v](init);
}else{
return new Error("async.select: out of range");
}
}).callback(init);
};
};
async.ifThen = function(cond, ifTrue, ifFalse){
// summary:
// Executes a condition, waits for it if necessary, and executes
// one of two functions.
return function(init){
return new Deferred().addCallback(cond).addCallback(function(v){
return (v ? ifTrue : ifFalse)(init);
}).callback(init);
};
};
async.loop = function(cond, body){
// summary:
// Executes a condition, waits for it if necessary, and executes
// the body, if truthy value was returned.
// Then it repeats the cycle until the condition function returns
// a falsy value.
return function(init){
var x, y = new Deferred(function(){ x.cancel(); });
function ifErr(v){ y.errback(v); }
function loop(v){
if(v){
x.addCallback(body).addCallback(setUp);
}else{
y.callback(v);
}
return v;
}
function setUp(init){
x = new Deferred().
addCallback(cond).
addCallback(loop).
addErrback(ifErr);
x.callback(init);
}
setUp(init);
return y;
};
};
})();
/*
Design decisions:
seq() - behaves like the normal Deferred callback chain.
par() - if error, all pending Deferreds are cancelled and the error is signaled,
otherwise return an array of all results.
any() - just like par() but only one result is returned.
select() - any error is returned, otherwise the selected result is returned.
loop() - any error is returned, otherwise the last result is returned.
*/
});
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