Boost C++ Libraries Home Libraries People FAQ More

PrevUpHomeNext
grammar::lut_chars::operator-

Return a new character set by subtracting.

Synopsis

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

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 [link url.ref.boost__urls__grammar__lut_chars.lut_chars `lut_chars`] consonants = [link url.ref.boost__urls__grammar__lut_chars.lut_chars `lut_chars`]( "abcdefghijklmnopqrstuvwxyz" ) - "aeiou" ;
Complexity

Constant.

Return Value

The new character set.

Parameters

Name

Description

cs0

A character set to join.

cs1

A character set to join.

Convenience header <boost/url/grammar.hpp>


PrevUpHomeNext