Return a new character set by subtracting.

Synopsis

Defined in header <boost/url/grammar/lut_chars.hpp>

friend constexpr lut_chars
operator-(
    lut_chars const& cs0,
    lut_chars const& cs1);

Description

This function returns a new character set which is formed from all of the characters in cs0 which are not in cs.

Example

This statement declares a character set containing all the lowercase letters which are not vowels:

constexpr lut_chars consonants = lut_chars("abcdefghijklmnopqrstuvwxyz") - "aeiou";

Complexity

Constant.

Return Value

The new character set.

Parameters

Convenience header <boost/url/grammar.hpp>