babel-plugin-transform-es2015-block-scoped-functions

What is babel-plugin-transform-es2015-block-scoped-functions?

The babel-plugin-transform-es2015-block-scoped-functions package is a Babel plugin that transforms ES2015 block-scoped function declarations into a form that is compatible with older JavaScript environments. This is particularly useful for ensuring that code using block-scoped functions can run in environments that do not natively support ES2015 features.

What are babel-plugin-transform-es2015-block-scoped-functions's main functionalities?

Transform Block-Scoped Functions

This feature transforms block-scoped function declarations into a form that is compatible with older JavaScript environments. In the example, the function `foo` is declared within a block scope, and the plugin ensures that this code can run in environments that do not support block-scoped functions.

const babel = require('@babel/core');
const code = `{
  function foo() { return 'bar'; }
}`;
const output = babel.transform(code, {
  plugins: ['transform-es2015-block-scoped-functions']
});
console.log(output.code);

Other packages similar to babel-plugin-transform-es2015-block-scoped-functions

babel-plugin-transform-es2015-block-scoping

This package transforms block-scoped variables (let and const) and block-scoped functions into a form that is compatible with older JavaScript environments. It is more comprehensive than babel-plugin-transform-es2015-block-scoped-functions as it handles both block-scoped variables and functions.

babel-plugin-transform-es2015-function-name

This package ensures that function names are properly assigned in all cases, which can be useful for debugging. While it does not specifically handle block-scoped functions, it complements babel-plugin-transform-es2015-block-scoped-functions by ensuring function names are preserved.

babel-plugin-transform-es2015-parameters

This package transforms ES2015 function parameters (default, rest, and destructuring parameters) into a form that is compatible with older JavaScript environments. It does not handle block-scoped functions specifically but is useful for ensuring broader compatibility of ES2015 function features.

README

babel-plugin-transform-es2015-block-scoped-functions

Babel plugin to ensure function declarations at the block level are block scoped.

Examples

In

{
  function name (n) {
    return n;
  }
}

name("Steve");

Out

{
  var _name = function _name(n) {
    return n;
  };
}

name("Steve");

Installation

npm install --save-dev babel-plugin-transform-es2015-block-scoped-functions

Usage

Via .babelrc (Recommended)

.babelrc

{
  "plugins": ["transform-es2015-block-scoped-functions"]
}

Via CLI

babel --plugins transform-es2015-block-scoped-functions script.js

Via Node API

require("babel-core").transform("code", {
  plugins: ["transform-es2015-block-scoped-functions"]
});