std::islower(std::locale)
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Defined in header
<locale>
template< class CharT >
bool islower( CharT ch, const locale& loc );
bool islower( CharT ch, const locale& loc );
Checks if the given character is classified as a lowercase alphabetic character by the given locale's std::ctype facet.
[edit] Parameters
ch
-
character
loc
-
locale
[edit] Return value
Returns true if the character is classified as lowercase, false otherwise.
[edit] Possible implementation
template<class CharT> bool islower(CharT ch, const std::locale & loc) { return std::use_facet <std::ctype <CharT>>(loc).is(std::ctype_base::lower, ch); }
[edit] Example
Demonstrates the use of islower() with different locales (OS-specific).
Run this code
#include <iostream> #include <locale> int main() { const wchar_t c = L'\u03c0'; // GREEK SMALL LETTER PI std::locale loc1("C"); std::cout << std::boolalpha << "islower('π', C locale) returned " << std::islower (c, loc1) << '\n' << "isupper('π', C locale) returned " << std::isupper (c, loc1) << '\n'; std::locale loc2("en_US.UTF8"); std::cout << "islower('π', Unicode locale) returned " << std::islower (c, loc2) << '\n' << "isupper('π', Unicode locale) returned " << std::isupper (c, loc2) << '\n'; }
Possible output:
islower('π', C locale) returned false
isupper('π', C locale) returned false
islower('π', Unicode locale) returned true
isupper('π', Unicode locale) returned false