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Callbacks

Across the documentation you will see the use of callbacks.

When a callback is accepted you can use a traditional function or a closure.

In we can use an array to reference a callback from object. This is similar to the syntax of PHP's call_user_func_array. The array is a simple array with two elements. The first element is the object and the second element is a function or a string with the name of a function.

var callback = [MyObject, "doThis"];

The function element is a string, EXC will look for a function on the object with that name if one is found it is executed. If the function element is an actual function it will be executed with the this scope set to the object on the first element.

Helper Functions

Check if a value is callable.

	var bool = core.isCallable(fn);

The most useful function is core.getCallback(), it gets a function from a value that may be a callable. This function returns undefined if the value is not callable or it can not be converted to a callable function. This function is useful to handle strings with controller actions or messages like "[aMessage]" or "[aController.message]".

 	var fn = core.getCallback(aValue);
 	if(fn) fn(arg1, arg2);

Executes a callback with passed arguments

	var returnValue = core.callback(fn, arg1, arg2);

Executes a callback with an array of arguments

	var args = [arg1, arg2];
	var returnValue = core.callbackWithArguments(fn, args);