NAME¶

std::iswspace - std::iswspace

Synopsis¶

Defined in header <cwctype>
int iswspace( wint_t ch );

Checks if the given wide character is a wide whitespace character as classified by
the currently installed C locale. In the default locale, the whitespace characters
are the following:

* Space (0x20, ' ')
* Form feed (0x0c, '\f')
* Line feed (0x0a, '\n')
* Carriage return (0x0d, '\r')
* Horizontal tab (0x09, '\t')
* Vertical tab (0x0b, '\v').

If the value of ch is neither representable as a wchar_t nor equal to the value of
the macro WEOF, the behavior is undefined.

Parameters¶

ch - wide character

Return value¶

Non-zero value if the wide character is a whitespace character, zero otherwise.

Notes¶

ISO 30112 defines POSIX space characters as Unicode characters U+0009..U+000D,
U+0020, U+1680, U+180E, U+2000..U+2006, U+2008..U+200A, U+2028, U+2029, U+205F, and
U+3000.

Example¶

Demonstrates the use of iswspace with different locales.

// Run this code

#include <clocale>
#include <cwctype>
#include <iostream>

void try_with(wchar_t c, const char* loc)
{
std::setlocale(LC_ALL, loc);
std::wcout << "isspace('" << c << "') in " << loc << " locale returned "
<< std::boolalpha << static_cast<bool>(std::iswspace(c)) << '\n';
}

int main()
{
const wchar_t EM_SPACE = L'\u2003'; // Unicode character 'EM SPACE'
try_with(EM_SPACE, "C");
try_with(EM_SPACE, "en_US.UTF8");
}

Output:¶

isspace(' ') in C locale returned false
isspace(' ') in en_US.UTF8 locale returned true

See also¶

isspace(std::locale) checks if a character is classified as whitespace by a locale
(function template)
isspace checks if a character is a space character
(function)
C documentation for
iswspace

ASCII values characters iscntrl isprint isspace isblank isgraph ispunct isalnum isalpha isupper islower isdigit isxdigit decimal hexadecimal octal iswcntrl iswprint iswspace iswblank iswgraph iswpunct iswalnum iswalpha iswupper iswlower iswdigit iswxdigit 0–8 \x0–\x8 \0–\10 control codes ≠0 0 0 0 0 0 0 0 0 0 0 0
(NUL, etc.) 9 \x9 \11 tab (\t) ≠0 0 ≠0 ≠0 0 0 0 0 0 0 0 0
whitespaces 10–13 \xA–\xD \12–\15 (\n, \v, \f, ≠0 0 ≠0 0 0 0 0 0 0 0 0 0
\r) 14–31 \xE–\x1F \16–\37 control codes ≠0 0 0 0 0 0 0 0 0 0 0 0 32 \x20 \40 space 0 ≠0 ≠0 ≠0 0 0 0 0 0 0 0 0 33–47 \x21–\x2F \41–\57 !"#$%&'()*+,-./ 0 ≠0 0 0 ≠0 ≠0 0 0 0 0 0 0 48–57 \x30–\x39 \60–\71 0123456789 0 ≠0 0 0 ≠0 0 ≠0 0 0 0 ≠0 ≠0 58–64 \x3A–\x40 \72–\100 :;<=>?@ 0 ≠0 0 0 ≠0 ≠0 0 0 0 0 0 0 65–70 \x41–\x46 \101–\106 ABCDEF 0 ≠0 0 0 ≠0 0 ≠0 ≠0 ≠0 0 0 ≠0 71–90 \x47–\x5A \107–\132 GHIJKLMNOP 0 ≠0 0 0 ≠0 0 ≠0 ≠0 ≠0 0 0 0
QRSTUVWXYZ 91–96 \x5B–\x60 \133–\140 [\]^_` 0 ≠0 0 0 ≠0 ≠0 0 0 0 0 0 0 97–102 \x61–\x66 \141–\146 abcdef 0 ≠0 0 0 ≠0 0 ≠0 ≠0 0 ≠0 0 ≠0 103–122 \x67–\x7A \147–\172 ghijklmnop 0 ≠0 0 0 ≠0 0 ≠0 ≠0 0 ≠0 0 0
qrstuvwxyz 123–126 \x7B–\x7E \172–\176 {|}~ 0 ≠0 0 0 ≠0 ≠0 0 0 0 0 0 0 127 \x7F \177 backspace ≠0 0 0 0 0 0 0 0 0 0 0 0
character (DEL)