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arashmilani/gist:4732488

Created February 7, 2013 17:13
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Trying to find much better way to assert Types in javascript rather than comparing types in string using typeof
Raw
gistfile1.js
function assertType(obj, type) {
return obj.constructor.name === type.name
}
console.info(assertType("test", String)); //true
console.info(assertType(1, String)); //false
console.info(assertType(1, Number)); //true
function Book(){};
function Desk(){};
var book = new Book();
console.info(assertType(book, Book)); //true
console.info(assertType(book, Desk)); //false
console.info(assertType([], Array)); //true
console.info(assertType(function(){}, Function)); //true
@miladr
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miladr commented Feb 7, 2013

var testObj=new Object();
console.info(assertType(testObj, Object)); //True

@miladr
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miladr commented Feb 7, 2013

console.info(assertType({}, Object)); //True

@arashmilani
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Note that there's NO WAY to beat "typeof" in performance.
Check it here for yourself: http://jsperf.com/am-type-assertion#run

@afshinm
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afshinm commented Feb 7, 2013

Geeks, here the updated gist with prototype: https://gist.github.com/afshinm/4733756

@arashmilani
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Thank you Afshin for the prototype version :)

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