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vamosrope14
14,932 PointsWhat's the difference between reassigning a value to a variable and creating multiple 'local' copies?
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2 Answers
Steven Parker
231,275 PointsThe re-assignment of a variable doesn't create copies of it, it simply changes the value it is holding.
The "copy" process is related to the scope of the variable. For a "var" variable, the variable shares the scope of the surrounding code, so that variable is "shared" and changes made in one place will be seen from the other. But a "let" variable is block scoped, so inside a loop each iteration has a different scope and gets a copy of the variable.
The difference might not be noticed except in cases like in the video, where the reference in the loop isn't used until after the loop has changed the value of the index.
vamosrope14
14,932 Points.