Turn an object into a argument style array (for use with child_process.spawn, for instance).

toArgumentArray.js

var _ = require('underscore')

/**
*  Takes an key-value hash and returns an array with
*  the following structure:
*
*  {key: 'val', foo: 'bar'}
*  => ['--key', 'val', '--foo', 'bar']
*/
var toArgumentArray = function(src) {
  return _.reduceRight(src, function(prev, val, key) {
    return prev.concat("--"+key, val)
  }, [])
}