100% type-safe curry() function written in TS

According to Wikipedia, "Currying is the technique of translating a function that takes multiple arguments into a sequence of families of functions, each taking a single argument".

It is essentially a programming style which favors reuse, by creating reusable functions from previous function (partial) calls.

This package provides a simple way to transform functions into their curried versions using a Higher-Order Function (HOF) called "curry()", while keeping the original function's signature, expecting the same parameters as the original function, but 1 parameter at a time (i.e. per call), until all parameters are finally supplied.

Features

• 100% type-safe
• Supports functions that have up to 30 parameters
• Fully compatible with JavaScript
• Very small (only 457 bytes gzipped after bundling)
• No external dependencies

Installation

Install from npm using your favorite package manager:

npm install @cdandrea/currying-ts

yarn add @cdandrea/currying-ts

pnpm install @cdandrea/currying-ts

Usage

Simply supply the function to be curried as the 1st parameter of the curry() HOF.

import { curry } from '@cdandrea/currying-ts'

const sum = curry((a: number, b: number) => a + b)

// `sum()` expects a number, corresponding to the
// original function's 1st parameter (`a`).
const sum10 = sum(10)
const sum20 = sum(20)

// `sum10()` also expects a number, corresponding
// to the original function's 2nd parameter (`b`).
console.log(sum10(5)) // Prints 15.
console.log(sum10(100)) // Prints 110.

// And so does `sum20()`, which also expects a number.
console.log(sum20(5)) // Prints 25.
console.log(sum20(100)) // Prints 120.

Notice that the curried function returned by curry() gets fully typed, expecting the same parameters as the original function, and in the same order, but in successive function calls.