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JavaScript

Posted by behar
behar
10,800 Points

Javascript variables

Hey guys! Quick question about variables in Javascript. So you can use var, let and const to set variables. Dont use var if you can avoid it. Use let if the variable can change and const if it cant. But then i noticed that you can actually declare variables just like you do in python. For instace:

test = "whatever"

That variable is just as valid as far as i can tell. One reason i am using it is because it seems that if i declare a variable with let inside a function, i cant acces that variable from outside the function, but i can if i declare it like above. Is there any reason why i shouldent use this kind of variable, and why have i never heard about it?

1 Answer

Steven Parker
Steven Parker
243,658 Points
Steven Parker
Steven Parker
243,658 Points

What you have there is an "implicit global declaration", which is not considered a good programming practice. If you really want a variable to be global, it should be declared outside the function using an appropriate declaration word.

Also, if your program is running in "strict" mode, implicit declarations become a syntax error.