Difference between revisions of "cpp/string/wide/towupper"
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===Notes=== | ===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 {{lc|std::towupper}}. | + | Only 1:1 character mapping can be performed by this function, e.g. the uppercase form of {{c/core|'ß'}} is (with some exceptions) the two-character string {{c/core|"SS"}}, which cannot be obtained by {{lc|std::towupper}}. |
[http://www.open-std.org/JTC1/SC35/WG5/docs/30112d10.pdf ISO 30112] specifies which pairs of Unicode characters are included in this mapping. | [http://www.open-std.org/JTC1/SC35/WG5/docs/30112d10.pdf ISO 30112] specifies which pairs of Unicode characters are included in this mapping. | ||
| Line 23: | Line 23: | ||
===Example=== | ===Example=== | ||
{{example | {{example | ||
| − | |The latin | + | |The latin {{enwiki|Long s|letter 'ſ' (U+017F)}} is the alternative lowercase form of {{c/core|'S'}} (U+0053). |
|code= | |code= | ||
#include <clocale> | #include <clocale> | ||
| Line 34: | Line 34: | ||
std::cout << std::hex << std::showbase; | std::cout << std::hex << std::showbase; | ||
| − | std::cout << "in the default locale, towupper(" << | + | std::cout << "in the default locale, towupper(" |
| + | << static_cast<std::wint_t>(c) << ") = " | ||
<< std::towupper(c) << '\n'; | << std::towupper(c) << '\n'; | ||
| + | |||
std::setlocale(LC_ALL, "en_US.utf8"); | std::setlocale(LC_ALL, "en_US.utf8"); | ||
| − | std::cout << "in Unicode locale, towupper(" << | + | std::cout << "in Unicode locale, towupper(" |
| + | << static_cast<std::wint_t>(c) << ") = " | ||
<< std::towupper(c) << '\n'; | << std::towupper(c) << '\n'; | ||
} | } | ||
Revision as of 13:25, 18 June 2023
| Defined in header <cwctype>
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| std::wint_t towupper( std::wint_t ch ); |
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Converts the given wide character to uppercase, if possible.
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.
Contents |
Parameters
| ch | - | wide character to be converted |
Return value
Uppercase version of ch or unmodified ch if no uppercase version is listed in the current C locale.
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.
Example
The latin letter 'ſ' (U+017F) is the alternative lowercase form of 'S' (U+0053).
Run this code
#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'; }
Output:
in the default locale, towupper(0x17f) = 0x17f in Unicode locale, towupper(0x17f) = 0x53
See also
| converts a wide character to lowercase (function) | |
| converts a character to uppercase using the ctype facet of a locale (function template) | |
| converts a character to uppercase (function) | |
| C documentation for towupper
| |
