std::towupper(3)

🎀 NAME 🎀

okay bestie, welcome to std::towupper(3) from the C++ Standard Libary — that's the manual name up top, fr fr 💅. This page is literally about std::towupper — std::towupper. iconic. no cap.

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🌸 Synopsis 🌸

Defined in header <cwctype>:

std::wint_t towupper( std::wint_t ch );

Converts the given wide character to uppercase, if possible ✨.

Warning, bestie: 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. do not test fate 💀.

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💅 Parameters 💅

• ch — wide character to be converted 🫶

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🫶 Return value 🫶

Uppercase version of ch or unmodified ch if no uppercase version is listed in the current C locale 🌸.

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🧚 Notes 🧚

Only 1:1 character mapping can be performed by this function, e.g. the uppercase form of 'ß' is (with some exceptions) the two-character string "SS", which cannot be obtained by std::towupper 😭.

ISO 30112 specifies which pairs of Unicode characters are included in this mapping 👑.

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✨ Example ✨

The latin letter 'ſ' (U+017F) is the alternative lowercase form of 'S' (U+0053) 🦋.

The page literally says // Run this code before the snippet, so here it is in all its glory:

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

int main()
{
    wchar_t c = L'\u017f'; // Latin small letter Long S ('ſ')

    std::cout << std::hex << std::showbase;
    std::cout << "in the default locale, towupper("
              << static_cast<std::wint_t>(c) << ") = "
              << std::towupper(c) << '\n';

    std::setlocale(LC_ALL, "en_US.utf8");
    std::cout << "in Unicode locale, towupper("
              << static_cast<std::wint_t>(c) << ") = "
              << std::towupper(c) << '\n';
}

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🌈 Output 🌈

in the default locale, towupper(0x17f) = 0x17f
in Unicode locale, towupper(0x17f) = 0x53

slay. the vibes are uppercase now 💖.

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🦋 See also 🦋

• towlower — converts a wide character to lowercase (function)
• toupper(std::locale) — converts a character to uppercase using the ctype facet of a locale (function template)
• toupper — converts a character to uppercase (function)
• C documentation for towupper

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source: http://cppreference.com, dated 2024.06.10, footer page name: std::towupper(3) — bye bestie, go uppercase responsibly 💖✨🎀