std::isxdigit(std::locale)
From cppreference.com
| Defined in header <locale>
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| template< class CharT > bool isxdigit( CharT ch, const locale& loc ); |
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Checks if the given character is classified as a hexadecimal digit by the given locale's std::ctype facet.
Contents |
[edit] Parameters
| ch | - | character |
| loc | - | locale |
[edit] Return value
Returns true if the character is classified as a hexadecimal digit, false otherwise.
[edit] Possible implementation
template<class CharT> bool isxdigit(CharT ch, const std::locale& loc) { return std::use_facet<std::ctype<CharT>>(loc).is(std::ctype_base::xdigit, ch); } |
[edit] Example
Run this code
#include <iostream> #include <locale> #include <string> #include <unordered_set> struct gxdigit_ctype : std::ctype<wchar_t> { std::unordered_set<wchar_t> 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) | |
| checks if a wide character is a hexadecimal character (function) |
