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std::towlower(3)	       C++ Standard Libary		std::towlower(3)

NAME
     std::towlower - std::towlower

Synopsis
	Defined in header <cwctype>
	std::wint_t towlower( std::wint_t ch );

	Converts the given wide character to lowercase, 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.

Parameters
	ch - wide character to be converted

Return value
	Lowercase version of ch or unmodified ch  if  no  lowercase  version  is
     listed in the
	current C locale.

Notes
	Only  1:1  character mapping can be performed by this function, e.g. the
     Greek
	uppercase letter 'IL' has two lowercase forms, depending on the position
     in a word:
	'I' and 'I'. A call to std::towlower cannot be used to obtain  the  cor-
     rect lowercase
	form in this case.

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

Example
     // Run this code

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

      int main()
      {
	  wchar_t c = L'\u0190'; // Latin capital open E ('AE')

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

Output:
      in the default locale, towlower(0x190) = 0x190
      in Unicode locale, towlower(0x190) = 0x25b

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

http://cppreference.com 	   2024.06.10			std::towlower(3)
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