std::regex_traits<CharT>::transform
Min standard notice:
Obtains the sort key for the character sequence [first,last), such that if a sort key compares less than another sort key with operator<, then the character sequence that produced the first sort key comes before the character sequence that produced the second sort key, in the currently imbued locale’s collation order.
# Declarations
template< class ForwardIt >
string_type transform( ForwardIt first, ForwardIt last) const;
# Parameters
first, last: a pair of LegacyForwardIterators which determines the sequence of characters to compare
# Return value
The collation key for the character sequence [first,last) in the currently imbued locale.
# Example
This section is incompleteReason: no example