babel-preset-flow

What is babel-preset-flow?

The babel-preset-flow npm package is a Babel preset that allows you to strip Flow type annotations from your JavaScript code. This is useful for projects that use Flow for type checking but need to compile the code to plain JavaScript for production.

What are babel-preset-flow's main functionalities?

Stripping Flow Type Annotations

This feature allows you to remove Flow type annotations from your code, making it suitable for production environments where type annotations are not needed.

/* Input: */
// @flow
function add(a: number, b: number): number {
  return a + b;
}

/* Output: */
function add(a, b) {
  return a + b;
}

Other packages similar to babel-preset-flow

babel-plugin-transform-flow-strip-types

This Babel plugin also strips Flow type annotations from your code. It is more granular than babel-preset-flow, allowing you to use it as part of a custom Babel configuration.

flow-remove-types

A standalone tool that removes Flow type annotations from your code. Unlike babel-preset-flow, it does not require Babel and can be used as a CLI tool or library.

typescript

TypeScript is a popular alternative to Flow for type checking in JavaScript. It provides a similar type system but is more widely adopted and has better support in the JavaScript ecosystem.

README

babel-preset-flow

Babel preset for all Flow plugins.

This preset includes the following plugins:

• transform-flow-strip-types

Example

In

function foo(one: any, two: number, three?): string {}

Out

function foo(one, two, three) {}

Installation

npm install --save-dev babel-preset-flow

Usage

Via .babelrc (Recommended)

.babelrc

{
  "presets": ["flow"]
}

Via CLI

babel --presets flow script.js

Via Node API

require("babel-core").transform("code", {
  presets: ["flow"]
});