var util = require('util') function Resource(options) { this.src = options.src this.dest = options.dest.shift() this.comm = options.comm this.mode = options.mode this.fallback = options.dest } Resource.prototype.shift = function() { if (this.fallback.length === 0) { throw new Error(util.format( 'Out of fallback locations for "%s"' , this.src )) } this.dest = this.fallback.shift() } module.exports = Resource