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<title>JavaScript Patterns</title>

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/* Title: Callback patterns

Description: when you pass function A to function B as a parameter, function A is a callback function

*/

var complexComputation = function () { /* do some complex stuff and return a node */ };

var findNodes = function (callback) {

var nodes = [];

// check if callback is callable

if (typeof callback !== "function") {

callback = false;

}

var node = complexComputation();

if (callback) {

callback(node);

}

nodes.push(node);

return nodes;

};

// a callback function

var hide = function (node) {

node.style.display = "none";

};

// find the nodes and hide them as you go

var hiddenNodes = findNodes(hide);

// you can also use an anonymous function, like this:

var blockNodes = findNodes(function (node) {

node.style.display = 'block';

});

// reference

// http://www.jspatterns.com/

// http://shop.oreilly.com/product/9780596806767.do?sortby=publicationDate

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