@babel/plugin-transform-explicit-resource-management

This plugin enables Babel to transform using declarations using handler = await read();.

Example

input.js

using handlerSync = openSync();
await using handlerAsync = await openAsync();

will be transformed to

output.js

try {
  var _usingCtx = babelHelpers.usingCtx();
  var handlerSync = _usingCtx.u(openSync());
  var handlerAsync = _usingCtx.a(await openAsync());
} catch (_) {
  _usingCtx.e = _;
} finally {
  await _usingCtx.d();
}

Try it on the REPL.

Installation

npm

npm install --save-dev @babel/plugin-transform-explicit-resource-management

Yarn

yarn add --dev @babel/plugin-transform-explicit-resource-management

pnpm

pnpm add --save-dev @babel/plugin-transform-explicit-resource-management

Usage

With a configuration file (Recommended)

babel.config.json

{
  "plugins": ["@babel/plugin-transform-explicit-resource-management"]
}

Via CLI

Shell

babel --plugins @babel/plugin-transform-explicit-resource-management script.js

Via Node API

JavaScript

require("@babel/core").transformSync("code", {
  plugins: ["@babel/plugin-transform-explicit-resource-management"]
});

References

• Proposal: ECMAScript Explicit Resource Management