Require Modules from the Command Line

io.js v1.6.0 introduces a new command line option: -r or --require, which can be used to pre-load modules at startup, see:

https://github.com/iojs/io.js/blob/v1.x/CHANGELOG.md#2015-03-19-version-160-chrisdickinson

I can think of one interesting use case: overriding the default behavior or console.log to perform deep inspection:

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// console.js
var util = require('util');
var log = console.log;
console.log = function (obj) {
  log(util.inspect(obj, { colors: true, depth: null }));
};

Now I can pre-load this script to have all console log show in better format:

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$ iojs -r /path/to/console.js app.js

Time to find out more use cases.