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Axel Perossa
13,930 PointsAbout the different values of 'i'
I get that the function in the event handler gets evaluated at the moment the user clicks the button, not when the for loop runs, and that's why the i variable, when declared with var, equals 10.
When using let each event handler gets a refence to its very own i, each with a different value. But why do they still exist when the button is pressed? I mean, I thought variables declared with let inside a loop only exist inside that loop. Then why after the loop ends, and the button gets clicked, those ten different i variables still can be accessed by the event handler?
Or is it that the function in the event handler gets a hard-coded value in the code, like
"button" + 5 + "has been pressed";
I don't get that part. Thanks!
Steven Parker I really understand your answers :D
1 Answer
Steven Parker
231,248 Points
As I understand it, a variable is only disposed of when all scopes it is available to cease to exist. While the loop itself may have completed, the loop created a handler function to which the variable is still available, so it continues to exist for that function.