I am against adding these functions, but for different reasons than Sara and George. If we add str_left and str_right then there should be a corresponding variant in mbstring. The byte-string functions are rarely useful. Adding these functions to mbstring unnecessarily complicates the extension for little to no gain. Another point is that if we decide to add them, then we will bikeshed forever in an unresolvable manner about the name. Should it be called str_left or strleft? Current functions don't have a naming convention, so using either variant will be wrong. Personally, I find substr to be more clear about the intent. I know that I am asking for a part of the string. Whereas str_left doesn't convey an action immediately. Without knowing its purpose I wouldn't know if it will pad the string from the left, strip characters from left, or take the leftmost part of the string. Don't take it the wrong way, but I think it's a waste of time to implement a function that doesn't even need a polyfill in the userland.
Regards, Kamil
