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std::basic_...find_last_of(3) C++ Standard Libarystd::basic_...find_last_of(3)

NAME
       std::basic_string::find_last_of - std::basic_string::find_last_of

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

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

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

	  Finds	the last character equal to one	of  characters	in  the	 given
       character sequence.
	  The  exact  search  algorithm	is not specified. The search considers
       only the	range
	  [0, pos]. If none of the characters in the given character  sequence
       is present in
	  the range, npos will be returned.

	  1) Finds the last character equal to one of characters in str.
	  2)  Finds the	last character equal to	one 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 last character equal to one of characters in  character
       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 last character 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 last character equal to one of char-
       acters 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 at which the	search is to finish
	  count	- length of character string identifying characters to	search
       for
	  s	 -  pointer  to	 a  character string identifying characters to
       search for
	  ch	- character to search for
	  t	- object (convertible to  std::basic_string_view)  identifying
       characters to
		  search for

Return value
	  Position  of	the  found  character  or 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()
	{
	    const std::string path = "/root/config";
	    auto const pos = path.find_last_of('/');
	    const auto leaf = path.substr(pos +	1);

	    std::cout << leaf << '\n';
	}

Output:
	config

	  Defect reports

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

	     DR	   Applied to	     Behavior as  published		  Cor-
       rect behavior
	  LWG  141  C++98      overload	(1) could only return npos  the	search
       range is
			      if pos >=	size()			   [0, size())
       in this case
	  LWG 847  C++98       there  was  no  exception  safety	 added
       strong exception
			      guarantee					safety
       guarantee
	  LWG 2064 C++11      overloads	(3,4) were noexcept	   removed
	  LWG 2946 C++17      overload (5) caused ambiguity in	   avoided  by
       making it a
			      some cases			   template
		   C++11      noexcept for overloads (4,5) were
	  P1148R0  C++17      accidentally dropped by		   restored
			      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_first_not_of find first absence of characters
			    (public member function)
	  find_last_not_of  find last absence of characters
			    (public member function)
			    find last occurrence of characters
	  find_last_of	       (public	  member    function	of    std::ba-
       sic_string_view<CharT,Traits>)

Category:
	    * conditionally noexcept

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

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