babel-plugin-define-function

A plugin for Babel 6 allows you to define dynamic variables at build time with functions.

Installation

$ npm install babel-plugin-define-function --save-dev

.babelrc

{
  "plugins": [
    ["define-function", "./path/to/config/file.js"]
  ]
}

Example

Given the following definitions:

var exec = require('child_process').execSync
var details = require('./package.json')
var buildNumber = 0
 
module.exports = {
    // Define a static version variable.
    __VERSION__: details.version,
    // Evaluate git commit at build time.
    __GIT_COMMIT__: function () {
        // This function will be called on each build.
            return exec('git rev-parse HEAD') + '-' + buildNumber++
    }
}

And the following file:

console.log('package version is ' + __VERSION__)
console.log('git build is ' + __GIT_COMMIT__)

becomes:

console.log('package version is ' + '1.0.0')
console.log('git build is ' + '0c25b7ea0ed7554b7da285907154b66a694c3060-0')

and on the second build (if watching):

console.log('package version is ' + '1.0.0')
console.log('git build is ' + '0c25b7ea0ed7554b7da285907154b66a694c3060-1')

Contributions

• Use npm test to run tests.

License

MIT