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std::basic_...irst_not_of(3)  C++ Standard Libary std::basic_...irst_not_of(3)

NAME
       std::basic_string::find_first_not_of		-	      std::ba-
       sic_string::find_first_not_of

Synopsis
	  size_type find_first_not_of( const basic_string& str,	   (1)	(noex-
       cept since C++11)
				       size_type pos = 0 ) const;      (const-
       expr since C++20)
	  size_type find_first_not_of( const CharT* s,
				       size_type pos, size_type	   (2) (const-
       expr since C++20)
	  count	) const;
	  size_type find_first_not_of( const CharT* s,		   (3) (const-
       expr since C++20)
				       size_type pos = 0 ) const;
	  size_type  find_first_not_of(	CharT ch, size_type pos	= 0 (4)	(noex-
       cept since C++11)
	  ) const;						       (const-
       expr since C++20)
	  template< class StringViewLike >

	  size_type							(since
       C++17)
	      find_first_not_of( const StringViewLike& t,	   (5) (const-
       expr since C++20)

				 size_type pos = 0 ) const
	  noexcept(/* see below	*/);

	  Finds	 the  first  character	equal to none of the characters	in the
       given character
	  sequence. The	search considers only the range	[pos, size()). If  all
       characters in
	  the range can	be found in the	given character	sequence, npos will be
       returned.

	  1) Finds the first character equal to	none of	characters in str.
	  2)  Finds  the  first	character equal	to none	of characters in range
       [s, s + count).
	  This range can include null characters.
	  If [s, s + count) is not a valid range, the behavior is undefined.
	  3) Finds the first character equal to	none of	characters in  charac-
       ter string pointed
	  to  by  s.  The length of the	string is determined by	the first null
       character using
	  Traits::length(s).
	  If [s, s + Traits::length(s))	is not a valid range, the behavior  is
       undefined.
	  4) Finds the first character not equal to ch.
	  5)  Implicitly  converts  t  to  a  string view sv as	if by std::ba-
       sic_string_view<CharT,
	  Traits> sv = t;, then	finds the first	character  equal  to  none  of
       characters in sv.
	  This overload	participates in	overload resolution only if
	  std::is_convertible_v<const StringViewLike&,
				std::basic_string_view<CharT, Traits>> is true
       and
	  std::is_convertible_v<const StringViewLike&, const CharT*> is	false.

	  In all cases,	equality is checked by calling Traits::eq.

Parameters
	  str	- string identifying characters	to search for
	  pos	- position for the search to start from
	  count	 - length of character string identifying characters to	search
       for
	  s	- pointer to a	character  string  identifying	characters  to
       search for
	  ch	- character identifying	characters to search for
	  t	 -  object (convertible	to std::basic_string_view) identifying
       characters to
		  search for

Return value
	  Position of the found	character  or  std::string::npos  if  no  such
       character is found.

Exceptions
	  1,4) Throws nothing.
	  5)
	  noexcept specification:
	  noexcept(std::is_nothrow_convertible_v<const	     T&,      std::ba-
       sic_string_view<CharT,
	  Traits>>)

	  If an	exception is thrown for	any reason, this function has  no  ef-
       fect (strong
	  exception safety guarantee).

Example
       // Run this code

	#include <iostream>
	#include <string>

	int main()
	{
	    //	Permit	uppercase  letters,  lowercase	letters	and numbers in
       macro names
	    const char*	pattern	= "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
				  "abcdefghijklmnopqrstuvwxyz"
				  "0123456789";

	    std::string	data = "1) %FIX, 2) %HACK, and 3) %TODO";
	    const std::string replacement = "%DONE%";

	    std::cout << "Before: " << data << '\n';

	    for	(std::string::size_type	first{}, last{};
		(first = data.find('%',	first))	!= std::string::npos;
		first += replacement.size())
	    {
		last = data.find_first_not_of(pattern, first + 1);
		if (last == std::string::npos)
		    last = data.length();

		// Now first at	'%' and	last is	one past end of	the found sub-
       string
		data.replace(first, last - first, replacement);
	    }

	    std::cout << "After: " << data << '\n';
	}

Output:
	Before:	1) %FIX, 2) %HACK, and 3) %TODO
	After: 1) %DONE%, 2) %DONE%, and 3) %DONE%

	  Defect reports

	  The following	behavior-changing defect reports were applied retroac-
       tively to
	  previously published C++ standards.

	     DR	      Applied	 to		 Behavior     as     published
       Correct behavior
	  LWG  847  C++98      there was no exception safety guarantee	 added
       strong exception
									safety
       guarantee
	  LWG 2064 C++11      overloads	(3,4)  were  noexcept		   re-
       moved
	  LWG	2946   C++17	    overload  (5)  caused  ambiguity  in  some
       avoided by making it a
			      cases					  tem-
       plate
	  P1148R0   C++11	noexcept  for overloads	(4,5) were	   re-
       stored
		   C++17      accidentally dropped by LWG2064/LWG2946

See also
	  find		    finds the first occurrence of the given substring
			    (public member function)
	  rfind		    find the last occurrence of	a substring
			    (public member function)
	  find_first_of	    find first occurrence of characters
			    (public member function)
	  find_last_of	    find last occurrence of characters
			    (public member function)
	  find_last_not_of  find last absence of characters
			    (public member function)
			    find first absence of characters
	  find_first_not_of    (public	  member    function	of    std::ba-
       sic_string_view<CharT,Traits>)

Category:
	    * conditionally noexcept

http://cppreference.com		  2024.06.10	  std::basic_...irst_not_of(3)

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