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

NAME
     std::isgraph - std::isgraph

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

	Checks	if  the  given character is graphic (has a graphical representa-
     tion) as
	classified by the currently installed C locale. In the default C locale,
     the
	following characters are graphic:

	  * digits (0123456789)
	  * uppercase letters (ABCDEFGHIJKLMNOPQRSTUVWXYZ)
	  * lowercase letters (abcdefghijklmnopqrstuvwxyz)
	  * punctuation characters (!"#$%&'()*+,-./:;<=>?@[\]^_`{|}~)

	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 has a graphical  representation  charac-
     ter, zero
	otherwise.

Notes
	Like  all other functions from <cctype>, the behavior of std::isgraph 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_isgraph(char ch)
      {
	  return std::isgraph(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_graphs(const std::string& s)
      {
	  return std::count_if(s.begin(), s.end(),
			    // static_cast<int(*)(int)>(std::isgraph)	      //
     wrong
			    // [](int c){ return std::isgraph(c); }	      //
     wrong
			    // [](char c){ return std::isgraph(c); }	      //
     wrong
			       [](unsigned char c){ return std::isgraph(c); } //
     correct
			      );
      }

Example
     // Run this code

      #include <cctype>
      #include <clocale>
      #include <iostream>

      int main()
      {
	  unsigned char c = '\xb6'; // the character A<paragraph> in ISO-8859-1

	  std::cout << "isgraph(\'\\xb6\', default C locale) returned "
		    << std::boolalpha << (bool)std::isgraph(c) << '\n';

	  std::setlocale(LC_ALL, "en_GB.iso88591");
	  std::cout << "isgraph(\'\\xb6\', ISO-8859-1 locale) returned "
		    << std::boolalpha << (bool)std::isgraph(c) << '\n';
      }

Possible output:
      isgraph('\xb6', default C locale) returned false
      isgraph('\xb6', ISO-8859-1 locale) returned true

See also
	isgraph(std::locale) checks if a character is classified as graphical by
     a locale
			     (function template)
	iswgraph	     checks if a wide character is a graphical character
			     (function)
	C documentation for
	isgraph

	     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::isgraph(3)
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