If you can't find a good implementation for an interface perhaps the problem is the interface. Inline the function, refactor, then express the result via re-usa

If you can't find a good implementation for an interface perhaps the problem is the interface. Inline the function, refactor, then express the result via re-usable components. Ultimately it is a problem of code re-use vs performance. If you want divine insight it is probably to use lazy evaluation, so for the example in the article express normalize as a generator.