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std::isblank(std::locale)

Defined in header <locale>
template< class CharT >
bool isblank( CharT ch, const locale& loc );
(since C++11)

Checks if the given character is classified as a blank 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 blank character, false otherwise.

Possible implementation

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

Example

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

#include <iostream>
#include <locale>
 
void try_with(wchar_t c, const char* loc)
{
    std::wcout << "isblank('" << c << "', locale(\"" << loc << "\")) returned "
               << std::boolalpha
               << std::isblank(c, std::locale(loc)) << '\n';
}
 
int main()
{
    const wchar_t IDEO_SPACE = L'\u3000'; // Unicode character 'IDEOGRAPHIC SPACE'
    try_with(IDEO_SPACE, "C");
    try_with(IDEO_SPACE, "en_US.UTF-8");
}

Possible output:

isblank(' ', locale("C")) returned false
isblank(' ', locale("en_US.UTF-8")) returned true

See also

(C++11)
checks if a character is a blank character
(function)
(C++11)
checks if a wide character is a blank character
(function)

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