NAME¶

std::islower(std::locale) - std::islower(std::locale)

Synopsis¶

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.

Parameters¶

ch - character
loc - locale

Return value¶

Returns true if the character is classified as lowercase, false otherwise.

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);
}

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

See also¶

islower checks if a character is lowercase
(function)
iswlower checks if a wide character is lowercase
(function)