std::towctrans

C++

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iswalnum iswalpha iswlower iswupper iswdigit iswxdigit iswblank (C++11) wctype iswctype	iswcntrl iswgraph iswspace iswprint iswpunct towlower towupper wctrans towctrans
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Defined in header <cwctype>
std::wint_t towctrans( std::wint_t wc, std::wctrans_t desc );

Maps the wide character wc using the current C locale's LC_CTYPE mapping category identified by desc.

If the value of ch is neither representable as a wchar_t nor equal to the value of the macro WEOF, the behavior is undefined.

Parameters

ch	-	the wide character to map
desc	-	the LC_CTYPE mapping, obtained from a call to std::wctrans

Return value

The mapped value of ch using the mapping identified by desc in LC_CTYPE facet of the current C locale.

Example

The following example demonstrates katakana to hiragana character mapping

Run this code

#include <clocale>
#include <cwctype>
#include <iostream>
#include <algorithm>

std::wstring tohira(std::wstring str)
{
    std::transform(str.begin(), str.end(), str.begin(), [](wchar_t c) {
         return std::towctrans(c, std::wctrans("tojhira"));
    });
    return str;
}

int main()
{
    std::setlocale(LC_ALL, "ja_JP.UTF-8");
    std::wstring kana = L"";
    std::wcout << "katakana characters " << kana
               << " are " << tohira(kana) << " in hiragana\n";
}

Output:

katakana characters  are  in hiragana

See also

wctrans

looks up a character mapping category in the current C locale (function)