Javascript Nested Function Performance

I have some nested functions such as var freak = function() { var die = function() { ... } die(this); } As far as I have learned, the die function will get created (alloca

Solution 1:

As far as I have learned, the die function will get created (allocated) each time freak is called.

Yes. This is true. A new function-object is created.

So if freak gets called a lot of time, that means a lot of memory will be wasted [...]

For some very small and normally inconsequential value of "wasted".

JavaScript engines are very efficient these days and can perform a wide variety of tricks/optimizations.

For instance, only the function-object (but not the actual function code!) needs to be "duplicated" internally.

[...] does that mean nested functions should be avoided entirely?

No. There is no"wasting" problem without an actual test-case that shows otherwise. This idiom (of nested and anonymous functions) is very common in JavaScript and very well-optimized for.

Nested functions provide many benefits including self-documenting code, smaller self-contained lexical scopes, and other code isolation/organization advantages.