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Running a callback with all arguments

How can I run a callback function with all its arguments when I don't know how many arguments are provided.

Let's take the following example:

function tryMe (param1, param2) {
    alert(param1 + " and " + param2);
}

function callbackTester (callback) {
    callback (arguments[1], arguments[2]);
}

callbackTester (tryMe, "hello", "goodbye");

callbackTester (tryMe, "hello", "goodbye", "seeYouLater");

How can I trigger a callback from callbackTester()

within a function so that it automatically calls all of its arguments?

Fiddle: http://jsfiddle.net/qj1rs29q/

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2 answers


This should suit your needs:

function callbackTester() {
    var args = Array.prototype.slice.call(arguments),
        callback = args.shift();
    callback.apply(this, args);
}


Fiddle

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ECMAScript6 introduces the so-called rest option . It allows you to refer to all other arguments that are not explicitly specified. Together with your function it will look like .apply 

function callbackTester (callback, ...args) {
    callback.apply(null, args);
}

// callback = tryme | args = ["hello", "goodbye"]
callbackTester(tryMe, "hello", "goodbye");


Today you can use ES6 features with transpilers like 6to5 .

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