:relfileprefix: ../../../../
[#boost-urls-grammar-lut_chars-operator_bitnot]

= xref:boost.adoc[pass:[boost]]::xref:boost/urls.adoc[pass:[urls]]::xref:boost/urls/grammar.adoc[pass:[grammar]]::xref:boost/urls/grammar/lut_chars.adoc[pass:[lut_chars]]::operator~


Return a new character set which is the complement of another character set.


== Synopsis

Declared in header `<https://www.github.com/boostorg/url/blob/develop/include/boost/url/grammar/lut_chars.hpp#L371[boost/url/grammar/lut_chars.hpp,window=blank_]>`

[source,cpp,subs="verbatim,macros,-callouts"]
----
constexpr
xref:boost/urls/grammar/lut_chars.adoc[lut_chars]
operator~() const noexcept;
----

== Description


This function returns a new character
set which contains all of the characters
that are not in `*this`.

=== Example

This statement declares a character set
containing everything but vowels:
[,cpp]
----
constexpr lut_chars not_vowels = ~lut_chars( "AEIOU" "aeiou" );
----

=== Complexity

Constant.

=== Exception Safety

Throws nothing.




== Return Value


The new character set.