< cpp‎ | locale
Defined in header <locale>
template< class CharT >
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).

#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

[edit] See also

checks if a character is lowercase
(function) [edit]
checks if a wide character is lowercase
(function) [edit]