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The C and C++ Include Header Files

/usr/include/c++/13/ext/pb_ds/detail/eq_fn/hash_eq_fn.hpp


$ cat -n /usr/include/c++/13/ext/pb_ds/detail/eq_fn/hash_eq_fn.hpp

     1	// -*- C++ -*-
     2	
     3	// Copyright (C) 2005-2023 Free Software Foundation, Inc.
     4	//
     5	// This file is part of the GNU ISO C++ Library.  This library is free
     6	// software; you can redistribute it and/or modify it under the terms
     7	// of the GNU General Public License as published by the Free Software
     8	// Foundation; either version 3, or (at your option) any later
     9	// version.
    10	
    11	// This library is distributed in the hope that it will be useful, but
    12	// WITHOUT ANY WARRANTY; without even the implied warranty of
    13	// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    14	// General Public License for more details.
    15	
    16	// Under Section 7 of GPL version 3, you are granted additional
    17	// permissions described in the GCC Runtime Library Exception, version
    18	// 3.1, as published by the Free Software Foundation.
    19	
    20	// You should have received a copy of the GNU General Public License and
    21	// a copy of the GCC Runtime Library Exception along with this program;
    22	// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
    23	// <http://www.gnu.org/licenses/>.
    24	
    25	// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.
    26	
    27	// Permission to use, copy, modify, sell, and distribute this software
    28	// is hereby granted without fee, provided that the above copyright
    29	// notice appears in all copies, and that both that copyright notice
    30	// and this permission notice appear in supporting documentation. None
    31	// of the above authors, nor IBM Haifa Research Laboratories, make any
    32	// representation about the suitability of this software for any
    33	// purpose. It is provided "as is" without express or implied
    34	// warranty.
    35	
    36	/**
    37	 * @file hash_eq_fn.hpp
    38	 * Contains 2 equivalence functions, one employing a hash value,
    39	 * and one ignoring it.
    40	 */
    41	
    42	#ifndef PB_DS_HASH_EQ_FN_HPP
    43	#define PB_DS_HASH_EQ_FN_HPP
    44	
    45	#include <utility>
    46	#include <ext/pb_ds/detail/types_traits.hpp>
    47	#include <debug/debug.h>
    48	
    49	namespace __gnu_pbds
    50	{
    51	  namespace detail
    52	  {
    53	    /// Primary template.
    54	    template<typename Key, typename Eq_Fn, typename _Alloc, bool Store_Hash>
    55	      struct hash_eq_fn;
    56	
    57	    /// Specialization 1 - The client requests that hash values not be stored.
    58	    template<typename Key, typename Eq_Fn, typename _Alloc>
    59	    struct hash_eq_fn<Key, Eq_Fn, _Alloc, false> : public Eq_Fn
    60	    {
    61	      typedef Eq_Fn 					   eq_fn_base;
    62	      typedef typename rebind_traits<_Alloc, Key>::const_reference
    63		key_const_reference;
    64	
    65	      hash_eq_fn() { }
    66	
    67	      hash_eq_fn(const Eq_Fn& r_eq_fn) : Eq_Fn(r_eq_fn) { }
    68	
    69	      bool
    70	      operator()(key_const_reference r_lhs_key, 
    71			 key_const_reference r_rhs_key) const
    72	      { return eq_fn_base::operator()(r_lhs_key, r_rhs_key); }
    73	
    74	      void
    75	      swap(const hash_eq_fn& other)
    76	      { std::swap((Eq_Fn&)(*this), (Eq_Fn&)other); }
    77	    };
    78	
    79	
    80	    /// Specialization 2 - The client requests that hash values be stored.
    81	    template<typename Key, class Eq_Fn, class _Alloc>
    82	    struct hash_eq_fn<Key, Eq_Fn, _Alloc, true> : public Eq_Fn
    83	    {
    84	      typedef typename _Alloc::size_type 		   size_type;
    85	      typedef Eq_Fn 					   eq_fn_base;
    86	      typedef typename rebind_traits<_Alloc, Key>::const_reference
    87		key_const_reference;
    88	
    89	      hash_eq_fn() { }
    90	
    91	      hash_eq_fn(const Eq_Fn& r_eq_fn) : Eq_Fn(r_eq_fn) { }
    92	
    93	      bool
    94	      operator()(key_const_reference r_lhs_key, size_type lhs_hash, 
    95			 key_const_reference r_rhs_key, size_type rhs_hash) const
    96	      {
    97		_GLIBCXX_DEBUG_ASSERT(!eq_fn_base::operator()(r_lhs_key, r_rhs_key) 
    98				      || lhs_hash == rhs_hash);
    99	
   100		return (lhs_hash == rhs_hash && 
   101			eq_fn_base::operator()(r_lhs_key, r_rhs_key));
   102	      }
   103	
   104	      void
   105	      swap(const hash_eq_fn& other)
   106	      { std::swap((Eq_Fn&)(*this), (Eq_Fn&)(other)); }
   107	    };
   108	  } // namespace detail
   109	} // namespace __gnu_pbds
   110	
   111	#endif