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@babel/plugin-transform-modules-systemjs

info

This plugin is included in @babel/preset-env under the modules option

This plugin transforms ECMAScript modules to SystemJS. Note that only the syntax of import/export statements (import "./mod.js") and import expressions (import('./mod.js')) is transformed, as Babel is unaware of different resolution algorithms between implementations of ECMAScript modules and SystemJS.

Example​

In

JavaScript
export default 42;

Out

JavaScript
System.register([], function(_export, _context) {
  return {
    setters: [],
    execute: function() {
      _export("default", 42);
    },
  };
});

For dynamic import support (import('./lazy.js').then(m => ...)), enable the @babel/plugin-syntax-dynamic-import plugin before this one.

Installation​

npm install --save-dev @babel/plugin-transform-modules-systemjs

Usage​

Without options:

babel.config.json
{
  "plugins": ["@babel/plugin-transform-modules-systemjs"]
}

With options:

babel.config.json
{
  "plugins": [
    [
      "@babel/plugin-transform-modules-systemjs",
      {
        // outputs SystemJS.register(...)
        "systemGlobal": "SystemJS"
      }
    ]
  ]
}

Via CLI​

Shell
babel --plugins @babel/plugin-transform-modules-systemjs script.js

Via Node API​

JavaScript
require("@babel/core").transformSync("code", {
  plugins: ["@babel/plugin-transform-modules-systemjs"],
});

Options​

moduleIds​

boolean defaults to !!moduleId

Added in: v7.9.0

Enables module ID generation.

moduleId​

string

Added in: v7.9.0

A hard-coded ID to use for the module. Cannot be used alongside getModuleId.

getModuleId​

(name: string) => string

Added in: v7.9.0

Given the babel-generated module name, return the name to use. Returning a falsy value will use the original name.

moduleRoot​

string

Added in: v7.9.0

A root path to include on generated module names.