using `with` and harmony proxies to automatically declare otherwise undefined variables

index.js

#!/usr/bin/env node --harmony-proxies

var Fake = function(name) {
  this.name = name
}

var y = {}
  , x = Proxy.create({
      has: function(target, name) { return true }
    , getPropertyDescriptor: function(name) {
        try { return eval(name) } catch(e) {
        var x = new Fake(name)
        return { value: x, 
              writable: true,
            enumerable: true,
          configurable: true }    
          }
        }
    })

var d
with(x) {
  d = hello
}

console.log('got', d)