Just because you have some helper function somewhere in your codebase doesn't mean somebody else is going to find it. It's not uncommon that you end up with mul

Just because you have some helper function somewhere in your codebase doesn't mean somebody else is going to find it. It's not uncommon that you end up with multiple versions of the same helper function. And even if you did reuse that code, you might end up with more work because while you can you use it in two places, the third place that also uses it now has slightly different requirements. Do you add a bool parameter to that function? Now you have two code paths in the function, is it still tested as well as you thought it would? Or you could inline it... You can't predict the future. It's not worth thinking along the lines of "but maybe somebody might use it later". Only if they really do is it time to act. Don't go looking for abstractions. Let them come to you.