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<title>JavaScript Patterns</title>

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// Title: 4 different ways to call function

var foo, bar, baz, myapp;

function foo(a, b) {

return [this, a, b];

};

// using () operator

// if the function is called without an explicit owner object

// `this` keyword will refers to global

//

// bar = [window, 1, 2]

bar = foo(1, 2);

console.log(bar);

myapp = {

baz: foo,

onemore: function() {

function insideTheClosure() {

return this;

}

return [this, insideTheClosure()]

}

};

// still using () operator

// but now baz function belongs to myapp object

//

// bar = [myapp, 1, 2]

bar = myapp.baz(1, 2);

console.log(bar);

// like in the first example we need to call function

// within myapp like myapp.baz()

// not just inside the object`s function

//

// bar = [myapp, window]

bar = myapp.onemore();

console.log(bar);

// using apply and call methods of the Function itself

// there are almost the same

// but apply could be useful in case we don't know arguments beforehand

//

// bar = [myapp, 1, 2]

bar = foo.call(myapp, 1, 2);

console.log(bar);

bar = foo.apply(myapp, [1, 2]);

console.log(bar);

/* Reference:

* http://devlicio.us/blogs/sergio_pereira/archive/2009/02/09/JavaScript-5-ways-to-call-a-function.aspx

*/

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