function forEach( str, clbk, thisArg ) {
	var i;
	for ( i = 0; i < str.length; i++ ) {
		clbk.call( thisArg, str[ i ], i, str );
	}
	return str;
}
Invokes a function for each UTF-16 code unit in a string.

@param {string} str - input string
@param {Function} clbk - function to invoke
@param {*} [thisArg] - execution context
@returns {string} input string

@example
function log( value, index ) {
    console.log( '%d: %s', index, value );
}

forEach( 'Hello', log );