javascript - How do I assign a value to a variable stored in an array? -


for example:

var = b = c = null; var array = [a, b, c]; var value = 5;

how assign value a using array, without having array[0] overwritten?

how assign value variable stored in array?

you can't.

i think have misconception here: javascript pass-by-value, i.e. array doesn't hold reference variable, holds value variable had @ moment array created.

when write [a, b, c] literally means "evaluate a, b , c , add values array". after array created, there no knowledge anymore values came from.

this makes sense, since same behavior if use literals or other expressions instead of variables: [1, 40 + 2, "foo"]. evaluates each expression , adds result array.


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