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  • Ahmed Elgendy thinks this is interesting:

Why don’t the parameter names have var in front of them? A parameter is a new variable right?

A:

A: Effectively yes. The function does all the work of instantiating the variable for you, so you don’t need to supply the var keyword in front of your parameter names.

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Cover of Head First JavaScript Programming

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Why is there not a variable type before the parameters in function declaration/definition unlike Java which is a very typed language?