typeOf method for better type checking

[yasinuslu]

I just came by a very good article then i thought it would be good to have a method like that in underscore.js

[yasinuslu]

I didn't realize npm test. Checking failure right away.

[yasinuslu]

seems like a known problem: http://stackoverflow.com/questions/14218670/why-are-null-and-undefined-of-the-type-domwindow
code:

console.log("testing typeOf null:", _.typeOf(null));
console.log("testing typeOf undefined:", _.typeOf());
console.log("testing typeOf string:", _.typeOf("foo"));
console.log("testing typeOf null with typeof operator:", typeof null);
console.log("toString for null:", ({}).toString.call(null));
console.log("toString for string:", ({}).toString.call("foo"));

npm test (phantomjs 1.9.0) output:

testing typeOf null: domwindow
testing typeOf undefined: domwindow
testing typeOf string: string
testing typeOf null with typeof operator: object
toString for null: [object DOMWindow]
toString for string: [object String]

Chrome 31.0.1650.63 output:

testing typeOf null: null
testing typeOf undefined: undefined
testing typeOf string: string
testing typeOf null with typeof operator: object
toString for null: [object Null]
toString for string: [object String]

[akre54]

Hi @yasinuslu, this has been brought up and declined a few times in the past (an early one being #269). I think the reasoning still applies here.

[yasinuslu]

Seems fair, thanks for fast reply.