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std::iscntrl(std::locale)

Defined in header <locale> 
template< class CharT >
bool iscntrl( CharT ch, const locale& loc );

Checks if the given character is classified as a control character by the given locale's std::ctype facet.

Parameters

ch - character
loc - locale

Return value

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

Possible implementation

template<class CharT>
bool iscntrl(CharT ch, const std::locale& loc)
{
    return std::use_facet<std::ctype<CharT>>(loc).is(std::ctype_base::cntrl, ch);
}

Example

Demonstrates the use of iscntrl() with different locales (OS-specific).

#include <iostream>
#include <locale>
 
int main()
{
    const wchar_t CCH = L'\u0094'; // Destructive Backspace in Unicode
 
    std::locale loc1("C");
    std::cout << "iscntrl(CCH, C locale) returned "
              << std::boolalpha << std::iscntrl(CCH, loc1) << '\n';
 
    std::locale loc2("en_US.UTF8");
    std::cout << "iscntrl(CCH, Unicode locale) returned "
              << std::boolalpha << std::iscntrl(CCH, loc2) << '\n';
}

Possible output:

iscntrl(CCH, C locale) returned false
iscntrl(CCH, Unicode locale) returned true

See also

checks if a character is a control character
(function)
checks if a wide character is a control character
(function)

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