transform-once

  

A basic helper to simplify relations among values. Optionally compatible with WeakValue too.

``js
import transformOnce from 'transform-once';

const $ = transformOnce(value => {
return {object: Math.random()};
});

// references are transformed once
$(globalThis) === $(globalThis):

// transformed values are returned too
$(globalThis) === $($(globalThis)):

$(globalThis);
// {object: 0.123456789}
`

$3

If the input needs to be referenced, it is possible to use WeakRef based utility, such as WeakValue to automatically cleanup once the related reference is gone.

`js
import transformOnce from 'transform-once';
import WeakValue from 'weak-value';

// pass as context all needed classes (which are these three)
const transform = transformOnce.bind({WeakMap, WeakSet, WeakValue});

// now create a transformer that works with primitives too
const $ = transform(value => ({[typeof value]: Math.random()}));

$(1) === $(1);
$(1) === $($(1));
$($) === $($($));
$(1);
// {number: 0.123456789}
`

Alternative, it is also possible to pass a Map instead, but it's up to the program to clear its content, whenever it's necessary.

`js
import transformOnce from 'transform-once';
const transform = transformOnce.bind({WeakMap, WeakSet, WeakValue: Map});

// same as before but primitives are not weakly referenced
const $ = transform(value => ({[typeof value]: Math.random()}));
``

By default this module does not provide any weakly reference mechanism so each time a primitive is passed along, it will be transformed.