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JavaScript Asynchronous Programming with JavaScript Understanding Promises Promises Review

The Global var "value" is passed and modified (!) by the functions call. But it's declared as a const !

How it's possible ?

3 Answers

Steven Parker
Steven Parker
229,582 Points

The original "value" is not modified, but a new value is computed using it which is then return‍ed. The new value eventually gets passed down to "finalValue" where it is logged, but it is never stored back into "value".

MSM KSD14
MSM KSD14
270 Points

This is very very interesting. So does that mean the resolve method have a closure in the global variable environment?

Steven Parker
Steven Parker
229,582 Points

This is an example of simple argument passing and is not related to closures.

MSM KSD14
MSM KSD14
270 Points

Oh i see, let me rewatch it again