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std::iswspace

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.

#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

checks if a character is classified as whitespace by a locale
(function template)
checks if a character is a space character
(function)
C documentation for iswspace
ASCII values characters

iscntrl
iswcntrl

isprint
iswprint

isspace
iswspace

isblank
iswblank

isgraph
iswgraph

ispunct
iswpunct

isalnum
iswalnum

isalpha
iswalpha

isupper
iswupper

islower
iswlower

isdigit
iswdigit

isxdigit
iswxdigit
decimal hexadecimal octal
0–8 \x0–\x8 \0–\10 control codes (NUL, etc.) ≠0 0 0 0 0 0 0 0 0 0 0 0
9 \x9 \11 tab (\t) ≠0 0 ≠0 ≠0 0 0 0 0 0 0 0 0
10–13 \xA–\xD \12–\15 whitespaces (\n, \v, \f, \r) ≠0 0 ≠0 0 0 0 0 0 0 0 0 0
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
QRSTUVWXYZ		 0 ≠0 0 0 ≠0 0 ≠0 ≠0 ≠0 0 0 0
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
qrstuvwxyz		 0 ≠0 0 0 ≠0 0 ≠0 ≠0 0 ≠0 0 0
123–126 \x7B–\x7E \172–\176 {|}~ 0 ≠0 0 0 ≠0 ≠0 0 0 0 0 0 0
127 \x7F \177 backspace character (DEL) ≠0 0 0 0 0 0 0 0 0 0 0 0

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