JavaScript: Can one use "Object.prototype.toString.call(obj)" for data-type detection? -

if 1 calls tostring-method of object call (for changing context) string returned. string contains data-type of value given call.

var obj = {}; var field = []; var str = 'abc'; var num = 3; var reg = /.*/; var bool = true; var notanumber = nan; var undef = undefined;  console.log(object.prototype.tostring.call(obj)); // [object object] console.log(object.prototype.tostring.call(field)); // [object array] console.log(object.prototype.tostring.call(str)); // [object string] console.log(object.prototype.tostring.call(num)); // [object number] console.log(object.prototype.tostring.call(reg)); // [object regexp] console.log(object.prototype.tostring.call(bool)); // [object boolean] console.log(object.prototype.tostring.call(notanumber)); // [object number] console.log(object.prototype.tostring.call(undefined)); // [object undefined] 

what can tinkering: beside usual javascript weirdness (nan number) seems work fine.

now ask myself:

if make function .split(/\s/) etc., returning data-type string use type-detection.

but makes me distrustful:

i have never seen programmers use object.prototype.tostring.call-construct way. use typeof or methods ...

so question is:

would function described above work expected?

or fail because of different javascript implementations in browser? or fail because of other reason?

according specifications @ mdn, object.prototype.tostring supported on browsers, should work consistently.

i point out detecting difference between array , object differentiate results using typeof:

edit 1

and reg variable detects object.

var obj = {};  var field = [];  var str = 'abc';  var num = 3;  var reg = /.*/;  var bool = true;  var notanumber = nan;  var undef = undefined;    console.log(typeof obj); // object  console.log(typeof field); // object  console.log(typeof str); // string  console.log(typeof num); // number  console.log(typeof reg); // object  console.log(typeof bool); // boolean  console.log(typeof notanumber); // number  console.log(typeof undefined); // undefined  //data original post:  console.log(object.prototype.tostring.call(obj)); // [object object]  console.log(object.prototype.tostring.call(field)); // [object array]  console.log(object.prototype.tostring.call(str)); // [object string]  console.log(object.prototype.tostring.call(num)); // [object number]  console.log(object.prototype.tostring.call(reg)); // [object regexp]  console.log(object.prototype.tostring.call(bool)); // [object boolean]  console.log(object.prototype.tostring.call(notanumber)); // [object number]  console.log(object.prototype.tostring.call(undefined)); // [object undefined]