Wrap a function without changing its name and other properties.

Function wrappers return a new function which means the original function's
name and other properties are usually lost. This module enhances them to keep
those properties instead.

The new function will also print the original function's body when stringified.

Function wrappers are commonly used in functional programming. They take a
function as input and return it wrapped. Examples include
memoizing or ensuring a function is
only called once.

Example

``js
import keepFuncProps from 'keep-func-props'
// Any function wrapper works
import memoize from 'lodash/memoize.js'

const betterMemoize = keepFuncProps(memoize)

const anyFunction = () => true

// Function name and other properties are kept
console.log(anyFunction) // [Function: anyFunction]
console.log(memoize(anyFunction)) // [Function: memoized]
console.log(betterMemoize(anyFunction)) // [Function: anyFunction]

// Function body is kept when stringified
console.log(String(anyFunction))
// () => true
console.log(String(memoize(anyFunction)))
// function() {
// var args = arguments,
// key = resolver ? resolver.apply(this, args) : args[0],
// cache = memoized.cache;
// ...
// }
console.log(String(betterMemoize(anyFunction)))
// / Wrapped with memoized() /
// () => true
`

Install

`bash
npm install keep-func-props
`

This package works in both Node.js >=18.18.0 and
browsers.

This is an ES module. It must be loaded using
an import or import() statement,
not require(). If TypeScript is used, it must be configured to
output ES modules,
not CommonJS.

Usage

`js
import keepFuncProps from 'keep-func-props'

// Any function wrapper works
const wrapper =
(anyFunction) =>
(...args) =>
anyFunction(...args)

// betterWrapper is like wrapper but it keeps the function properties
const betterWrapper = keepFuncProps(wrapper)
`

keepFuncProps(wrapper)

wrapper: (anyFunction, [...args]) => newFunction\
_Returns_: new wrapper

A function wrapper is passed as argument. A copy of it is returned.

See also

- mimic-function: same but
for functions that do not wrap other functions.

Support

For any question, _don't hesitate_ to submit an issue on GitHub.

Everyone is welcome regardless of personal background. We enforce a
Code of conduct in order to promote a positive and
inclusive environment.

Contributing

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