I want to create a block scoped variable in javascript using var keyword.
I don't want to create using let keyword ecma6. As it will not support all browsers.
Is there a way to achieve this through some best and generic way?
usecase: I want to use this in for loop so that for every iteration it will create a new scope.
Create a "block" with an IIFE like so:
(function () {
var x = "whatever";
// x is scoped to only within this "block"
// block code
})()
For use in a for loop to maintain scope:
for (var i = 0; i < l; i++) {
(function (i) {
var x = "whatever";
// x is scoped to only within this "block"
// block code
})(i)
}
if (x){var ...} becomes (function(){if (x){var ...}}())?
if, the block is inside, so the IIFE would be inside the if block if you want to replicate let behaviori parameter does not refer to the same identifier as the i variable outside the IIFE. If you were to rename the i parameter of the function, you would see that is the case. Keeping the names the same is done simply for convenience.
.forEach().letorconst. Everything else is only a workaround and most of the time also more complex thanforEach.