Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. — Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

This is the documentation for a snapshot of the develop branch, built from commit 89872211d7.

Return true if ch is in the character set.

constexpr bool
operator()(
    unsigned char ch) const;

This function returns true if the character ch is in the set, otherwise it returns false.

Constant.

Throws nothing.

Name	Description
`ch`	The character to test.