What is compose-function?
The compose-function npm package provides utility functions for function composition, allowing you to combine multiple functions into a single function. This is particularly useful in functional programming paradigms where you want to create complex operations by combining simpler ones.
What are compose-function's main functionalities?
compose
The `compose` function allows you to combine multiple functions into a single function. In this example, `addThenMultiply` first adds 1 to the input and then multiplies the result by 2.
const compose = require('compose-function');
const add = x => x + 1;
const multiply = x => x * 2;
const addThenMultiply = compose(multiply, add);
console.log(addThenMultiply(5)); // Output: 12
pipe
The `pipe` function is similar to `compose` but applies functions from left to right. In this example, `multiplyThenAdd` first multiplies the input by 2 and then adds 1.
const { pipe } = require('compose-function');
const add = x => x + 1;
const multiply = x => x * 2;
const multiplyThenAdd = pipe(add, multiply);
console.log(multiplyThenAdd(5)); // Output: 11
Other packages similar to compose-function
lodash
Lodash is a popular utility library that provides a wide range of functions for common programming tasks, including function composition. The `_.flow` and `_.flowRight` methods in Lodash offer similar functionality to `compose` and `pipe` in compose-function.
ramda
Ramda is a functional programming library for JavaScript that emphasizes immutability and side-effect-free functions. It provides `R.compose` and `R.pipe` functions, which are similar to the compose-function package but come with additional functional programming utilities.
redux
Redux is a state management library for JavaScript applications. It includes a `compose` function that is often used to apply multiple middleware functions in a Redux store. While its primary focus is state management, its `compose` function can be used similarly to the compose-function package.
Compose-Function
Compose a new function from smaller functions f(g(x))
Installation
npm install compose-function
Usage
Basic usage
var compose = require('compose-function');
var composition = compose(sqr, add2);
composition(2)
compose(sqr, inc)(2);
compose(inc, sqr)(2);
Sweetjs
var composition = sqr ... add2;
composition(2)
$ sjs -m compose-function/macro yourfile.js
with curry
var compose = require('compose-function');
var curry = require('chickencurry');
function add(x, y) {
return x + y;
}
compose(
curry(add, 6),
sqr,
curry(add, 2)
);
var myFunc = curry(add, 6) ...
sqr ...
curry(add, 2)
compose(
curry(map, curry.__, sqr),
curry(filter, curry.__, even)
)([1,2,3,4,5,6,7,8])