Documentation unclear of how the memoizer is used

[Mr-Wallet]

The README describes how createSelectorCreator can be used to override the defaultMemoizer and how it will be called with the resultFunc and additional memoizeOptions. However, if my reading of the source code is correct, it's also called before calling the input functions to short-circuit their evaluation, and that isn't called with the memoizeOptions. These are important details for implementing a custom memoizer, so it seems like an oversight in the documentation.

[srubin]

This bit me recently. I'd appreciate being able to specify a different memoize function for the two purposes. I guess I could do this using memoizeOptions:

function memoizeInputArgs(fn) { /* ... */ }
function memoizeResultArgs(fn) { /* ... */ }

const selector = createSelectorCreator((fn, isResultFunction) =>
  isResultFunction ? memoizeResultArgs(fn) : memoizeInputArgs(fn), true)
);

but it might be cleaner to allow passing a second memoize function to createSelectorCreator.

[srubin]

I ended up with this slightly more fleshed-out version:

type MemoizeFn = (func: Function, option1?: any, option2?: any, option3?: any) => any;

export function myCreateSelectorCreator(
    memoizeResultFnArgs: MemoizeFn,
    memoizeResultFnArgsOptions: any[] = [],
    memoizeInputFnArgs: MemoizeFn = defaultMemoize,
    memoizeInputFnArgsOptions: any[] = [],
) {
    function memoize(fn: Function, areResultArgs: boolean) {
        if (areResultArgs) {
            return memoizeResultFnArgs(fn, ...memoizeResultFnArgsOptions);
        }
        return memoizeInputFnArgs(fn, ...memoizeInputFnArgsOptions);
    }
    return createSelectorCreator(
        memoize,
        true, // only passed to `memoize` for result args, not input args
    );
}

[markerikson]

This is mostly a duplicate of #376 and related to #359 .

[aryaemami59]

This one has been resolved by #636.