String#extract

gistfile1.js

/* relies on Craft.js */

Object.extend(String.prototype, {
  extract : function (context){ 
    return this.split(".").fold(function(a,b){ if(a) return b in a ? a[b] : undefined}, context || window )
  }
})

"document.body".extract() // HTMLBodyElement
"document.body.foo.bar.baz".extract() // undefined
"foo.bar.baz".extract({
  foo : {
    bar : {
      baz : "foo"
    }
  }
}) // foo