if-webpack-loader

Conditional compilation for webpack. Inspired by ifdef-loader.

Example & Usage

src/index.js

// #if PRODUCTION
  // #if OS === 'windows'
  win_main();
  /* #elif OS === 'macos'
  mac_main();
  */
  // #endif
// #endif

webpack.config.js

module.exports = {
  mode: 'production',
  module: {
    rules: [
      {
        test: /\.js$/,
        use: [
          {
            loader: 'if-webpack-loader',
            options: {
              PRODUCTION: true,
              OS: 'macos',
            },
          },
        ],
      },
    ],
  },
};

dist/main.js

mac_main();

Feature

if-webpack-loader supports multi-line comments (e.g. /* #if ... */) as well as single-line comments (e.g. // #if ...).

You can comment out #if / #elif / #else clauses using multi-line comments to suppress errors from vscode or eslint.

Code with errors from vscode or eslint:

// #if OS === 'android'
import { debug } from 'awesome-debugger-for-android';
// #else
import { debug } from 'ordinary-debugger';
// #endif
debug();

Code without errors from vscode or eslint:

// #if OS === 'android'
import { debug } from 'awesome-debugger-for-android';
/* #else
import { debug } from 'ordinary-debugger';
*/
// #endif
debug();

Limitation

Because if-webpack-loader is not aware of string literals, comments in string literals (e.g. "Hello, // #if world!") might cause unexpected errors.

Author

iorate

License

MIT License