what is some real use of checking identical type ===

Answer 1

Normaly when you check variables you expect them to be of some type.

An Example: Your code manages users and you need a value to be a number (probably Integer) for example the age. You dont want it to suddenly be a string. And even though it often wouldnt matter it would show that there is an inconsistency in your code and that is never a good thing.

You definetly want to check the type. :)

I found you more reference here that explains it in the very detail: http://stackoverflow.com/questions/359494/which-equals-operator-vs-should-be-used-in-javascript-comparisons#359509

Have a look at it. Its very well formulated.

Here is an excerpt:
'' == '0' // false
0 == '' // true
0 == '0' // true

false == 'false' // false
false == '0' // true

false == undefined // false
false == null // false
null == undefined // true

' \t\r\n ' == 0 // true

It shows that == not only doesnt show inconsistency in your own code but also works inconsistent itself and is hard to remember when it does what.

Answer 2

You actually should only use ===.
The difference between '==' an '===' is its strictness.

//Example Variables to show case
var nr = 23;
var nrInAString = '23';

'==' for Example will give you true when:
if (nr == nrInAString) document.log('They are equal');
// output is 'They are equal'

'===' will check the type of the variables and will give you false:
if (nr === nrInAString) document.log('They are equal');
// wont output 'They are equal'

Hope that helped.

Answer 3

I got a scenario like number and a number string comparison

Answer 4

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