dotted string access

// key is a string of possibly dotted accessors
function prop(obj, key) {
  var keys = key.split('.');
  for (var i in keys) {
    if (!obj) break;
    obj = obj[keys[i]];
  }
  return obj;
}


// test code


var assert = require('assert');

obj = {
  foo: {
    bar: 23,
    baz: 42
  },
  fred: 99,
  a: { b: { c: { d: "deeep" } } }
}

assert.equal(prop(obj, 'foo.bar'), 23)
assert.equal(prop(obj, 'foo.baz'), 42)
assert.equal(prop(obj, 'foo.quux'), undefined)
assert.deepEqual(prop(obj, 'foo'), {"bar": 23, "baz": 42})
assert.equal(prop(obj, 'fred'), 99)
assert.equal(prop(obj, 'nothing'), undefined)
assert.equal(prop(obj, 'a.b.c.d'), "deeep")