deepRead fast, nested JS expression reader

/**
 * Performs nested property lookups without eval or switch(e.length), removed try {} catch(){}
 * due to performance considerations.  Uses a short-circuit for invalid properties & returns false.
 *
 * data = {
 *   a1: { b1: "hello" },
 *	 a2: { b2: { c2: "world" } }
 *	}
 *
 * deepRead(data, "a1.b1") => "hello"
 *
 * deepRead(data, "a2.b2.c2") => "world"
 * 
 * deepRead(data, "a1.b2") => false
 * 
 * deepRead(data, "a1.b2.c2.any.random.number.of.non-existant.properties") => false
 *
 * @param {object} data - The collection to iterate over
 * @param {string} expression - The string expression to evaluate
 *
 * @return {various | boolean} retVal - Returns the found property or false if not found
 *
 */
var deepRead = function (data, expression) {

	// Cache a copy of the split expression, then set to exp
	var exp = expression.split('.'), retVal;

	// Recursively read the object using a do-while loop, uses short-circuit for invalid properties
	do {
		retVal = (retVal || data)[exp.shift()] || false;
	} while (retVal !== false && exp.length);

	// Return our retVal or false if not found
	return retVal || false;

};