Checking for Titanium API objects

index.js

var jsObject = {
	foo: 'bar'
};

var tiObject = Ti.UI.create2DMatrix();

function isJsObject(obj) {
	return  typeof obj.__proto__ !== 'undefined';
}

console.log('jsObject: ' + (isJsObject(jsObject) ? 'yes' : 'no'));
console.log('tiObject: ' + (isJsObject(tiObject) ? 'yes' : 'no'));

Nice technique. Minor typos in isJsObject(jtibject) should be

console.log('tiObject: ' + (isJsObject(tiObject) ? 'yes' : 'no'));

Did you mean __proto__?

Indeed @yuchi, thx!

Updated the above and tested in Triple:

> isJsObject(Object.create(null));
true
> isJsObject({});
true
> isJsObject([]);
true
> isJsObject('');
true
> isJsObject(Ti.UI.createWindow());
false
> isJsObject(Ti.UI.create2DMatrix);
false
> isJsObject(new Object());
true
> isJsObject(new Date());
true
> isJsObject(function() {});
true

Oh gosh:

console.log(Object.create(null)._proto__ === undefined); // true
console.log(Object.create(null)._proto__ === null); // false
console.log(typeof Object.create(null)._proto__); // "undefined"

var temp = Object.create(null)._proto__;
console.log(temp === undefined); // false, WAT?
console.log(temp === null); // true, WAT?!?!!
console.log(typeof temp); // "object"

Strange indeed, but:

> var _isObject = function(obj) { var type = typeof obj; return type === 'function' || type === 'object' && !!obj; };
undefined
> _isObject(Object.create(null).__proto__);
false
> var temp = Object.create(null).__proto__; _isObject(temp);
false

I guess as long as you know you have an object and need to test if it's not a Ti one... the code as I have it now works ok ;)

Looks like that as an expression (or part of one) it returns undefined, but when passed around (assignment, or function invocation) is null.

I feel stupid. _proto__ with one _…

function isJSObject(o) { return !!(o && o.__proto__ !== undefined); };

works flawlessy…