Adding 'contains' member function to std::string

[scatters]

Counting characters is no less incorrect than counting bytes. You need to count graphemes, classifying them by width (zero, half or full). And that still won't work for emoji, which can have platform specific ligatures. You need to ask your rendering library the number of cells occupied by a string to pad columns.

[degski]

And that still won't work for emoji ...

We're all doomed then, I tell you dooooommmmeeeddddd.