more naming

[Andrei Alexandrescu]

OK, so we have replace(haystack, needle, nail) which replaces _all_ 
occurrences of needle in haystack with nail. How would you call a 
function that replaces only the _first_ occurrence of needle with nail?

Must be a distinct function, not a runtime parameter to the existing 
function. This is because the function that replaces only one occurrence 
only requires nail to be an input range.


Andrei