well using default would assume we 'll only get braces, I think the best practice is to not trust anyone and here reserve default to log an error to all the fuckers who'll use wrongly this function XD

in most cases yes, but there is exceptions such as emmbeded devices with limited amount of memory. I think you need to write ur code according to the platform y're writting for

goôöòóœøōõl!

Technically, no.
string::npos is the preferred usage though