javascript - What is context in _.each(list, iterator, [context])? -

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i new underscore.js. purpose of [context] in _.each()? how should used?

the context parameter sets value of this in iterator function.

var someotherarray = ["name","patrick","d","w"];  _.each([1, 2, 3], function(num) {      // in here, "this" refers same array "someotherarray"      alert( this[num] ); // num value array being iterated                         //    this[num] gets item @ "num" index of                         //    someotherarray. }, someotherarray);

working example: http://jsfiddle.net/a6rx4/

it uses number each member of array being iterated item @ index of someotherarray, represented this since passed context parameter.

if not set context, this refer window object.


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