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std::isspace(3) 	       C++ Standard Libary		 std::isspace(3)

NAME
     std::isspace - std::isspace

Synopsis
	Defined in header <cctype>
	int isspace( int ch );

	Checks	if  the given character is 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')

	The behavior is undefined if the value of ch is not representable as un-
     signed char
	and is not equal to EOF.

Parameters
	ch - character to classify

Return value
	Non-zero value if the character is a whitespace character,  zero  other-
     wise.

Notes
	Like  all other functions from <cctype>, the behavior of std::isspace is
     undefined if
	the argument's value is neither representable as unsigned char nor equal
     to EOF. To
	use these functions safely with plain chars (or signed chars), the argu-
     ment should
	first be converted to unsigned char:

      bool my_isspace(char ch)
      {
	  return std::isspace(static_cast<unsigned char>(ch));
      }

	Similarly, they should not be directly	used  with  standard  algorithms
     when the
	iterator's value type is char or signed char. Instead, convert the value
     to unsigned
	char first:

      int count_spaces(const std::string& s)
      {
	  return std::count_if(s.begin(), s.end(),
			    // static_cast<int(*)(int)>(std::isspace)	      //
     wrong
			    // [](int c){ return std::isspace(c); }	      //
     wrong
			    // [](char c){ return std::isspace(c); }	      //
     wrong
			       [](unsigned char c){ return std::isspace(c); } //
     correct
			      );
      }

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

	     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  0a8	  \x0a\x8      \0a\10	  control  codes    a  0
     0	       0	 0	  0	   0	    0	     0	      0        0
     0	      0
				   (NUL,   etc.)    9	      \x9	     \11
     tab  (\t)	      a 0	0	 a 0	   a 0	     0	      0        0
     0	      0        0	0	 0
				   whitespaces	 10a13	   \xAa\xD	 \12a\15
     (\n,  \v,	\f,    a 0	 0	  a 0	    0	     0	      0        0
     0	      0        0	0	 0
				   \r)	14a31	 \xEa\x1F     \16a\37	 control
     codes    a  0	 0	  0	   0	    0	     0	      0        0
     0	       0	 0	   0   32	 \x20	       \40	   space
     0	       a  0	   a  0        a  0	   0	     0	      0        0
     0	      0        0	0 33a47   \x21a\x2F   \41a\57	 !"#$%&'()*+,-./
     0	       a  0	   0	     0	       a  0	   a  0       0        0
     0	      0 	0	  0  48a57    \x30a\x39    \60a\71    0123456789
     0	       a  0	   0	     0	       a  0	   0	     a 0       0
     0	      0        a 0	  a  0	58a64	 \x3Aa\x40    \72a\100	 :;<=>?@
     0	       a  0	   0	     0	       a  0	   a  0       0        0
     0	       0	 0	   0  65a70	\x41a\x46     \101a\106   ABCDEF
     0	       a  0	   0	     0	       a  0	  0	   a 0	     a 0
     a 0       0	0	 a 0 71a90    \x47a\x5A    \107a\132  GHIJKLMNOP
     0	       a  0	   0	     0	       a  0	  0	   a 0	     a 0
     a 0       0	0	 0
				   QRSTUVWXYZ  91a96	 \x5Ba\x60     \133a\140
     [\]^_`	      0        a 0	 0	  0	   a 0	     a 0       0
     0	      0        0	0	 0 97a102  \x61a\x66   \141a\146  abcdef
     0	       a  0	   0	     0	       a  0	  0	   a 0	     a 0
     0	      a 0	0	 a 0 103a122  \x67a\x7A    \147a\172  ghijklmnop
     0	       a  0	   0	     0	       a  0	  0	   a 0	     a 0
     0	      a 0	0	 0
				   qrstuvwxyz 123a126 \x7Ba\x7E   \172a\176 {|}~
     0	      a 0	 0	   0	     a	0	 a  0	     0	       0
     0	       0	 0	   0  127      \x7F	    \177       backspace
     a 0       0	0	 0	  0	   0	    0	     0	       0
     0	      0        0
				   character (DEL)

http://cppreference.com 	   2024.06.10			 std::isspace(3)

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