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JavaScript AJAX Basics Programming AJAX Parsing JSON Data

Posted by Peter Donaghy
Peter Donaghy
3,875 Points

var, let or const?

Is there a reason we use var here rather than let or const?

1 Answer

Steven Parker
Steven Parker
231,236 Points
Steven Parker
Steven Parker
231,236 Points

This course was released in 2014, before "let" and "const" were officially part of the language. If it were being recorded today this video would likely use "const" instead.

However, that said, I still personally like to use "var" for global variables (such as in this example) to distinguish them from those in a more limited scope.

Common reasons for choosing "var" in modern code have to do with the differences in the way it handles scope and hoisting. For more details, see these MDN pages on let and var.

Peter Donaghy
Peter Donaghy
3,875 Points

Ok great, thanks for the reply.