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  • Ahmed Elgendy thinks this is interesting:

It is a little subtle. First of all, you’re right—whether you use a function declaration or a function expression, you end up with a function. But there are some important differences between the two. For one, with a declaration, a function is created and setup before the rest of the code gets evaluated. With a function expression, a function is created as the code executes, at runtime.

Another difference has to do with function naming—when you use a declaration, the function name is used to create and set up as a variable that refers to the function. And, when you use a function expre...


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Another aspect of another major difference between function declaration and function expression?
In function expressions, functions do not have names but in function declarations, function have names.