std::isxdigit(std::locale) - cppreference.com (original) (raw)

| | | | | ---------------------------------------------------------------------- | | | | template< class CharT > bool isxdigit( CharT ch, const locale& loc ); | | |

Checks if the given character is classified as a hexadecimal digit by the given locale's std::ctype facet.

[edit] Parameters

[edit] Return value

Returns true if the character is classified as a hexadecimal digit, false otherwise.

[edit] Possible implementation

[edit] Example

#include #include #include #include   struct gxdigit_ctype : std::ctype { std::unordered_set greek_digits{L'α', L'β', L'γ', L'δ', L'ε', L'ζ'};   bool do_is(mask m, char_type c) const override { return (m & xdigit) && greek_digits.contains(c) ? true // 6 first Greek small letters will be classified as digits : ctype::do_is(m, c); // leave the rest to the parent class } };   int main() { std::wstring text = L"0123456789abcdefABCDEFαβγδεζηθικλμ"; std::locale loc(std::locale(""), new gxdigit_ctype);   std::locale::global(std::locale("en_US.utf8")); std::wcout.imbue(std::locale());   std::wcout << "Hexadecimal digits in text: "; for (const wchar_t c : text) if (std::isxdigit(c, loc)) std::wcout << c << L' '; std::wcout << L'\n';   std::wcout << "Not hexadecimal digits in text: "; for (const wchar_t c : text) if (not std::isxdigit(c, loc)) std::wcout << c << L' '; std::wcout << L'\n'; }

Output:

Hexadecimal digits in text: 0 1 2 3 4 5 6 7 8 9 a b c d e f A B C D E F α β γ δ ε ζ Not hexadecimal digits in text: η θ ι κ λ μ

[edit] See also

| | checks if a character is a hexadecimal character (function) [edit] | | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | | checks if a wide character is a hexadecimal character (function) [edit] |