A function that returns its first argument. This function is useful when writing code in the functional style.
function transformer(transformationFn, value) {
return (transformationFn || angular.identity)(value);
};
// E.g.
function getResult(fn, input) {
return (fn || angular.identity)(input);
};
getResult(function(n) { return n * 2; }, 21); // returns 42
getResult(null, 21); // returns 21
getResult(undefined, 21); // returns 21