hash_find_neg.cc

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// { dg-do compile }
// -*- C++ -*-

// Copyright (C) 2005 Free Software Foundation, Inc.
//
// This file is part of the GNU ISO C++ Library.  This library is free
// software; you can redistribute it and/or modify it under the
// terms of the GNU General Public License as published by the
// Free Software Foundation; either version 2, or (at your option)
// any later version.

// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License along
// with this library; see the file COPYING.  If not, write to the Free
// Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
// USA.

// As a special exception, you may use this file as part of a free software
// library without restriction.  Specifically, if other files instantiate
// templates or use macros or inline functions from this file, or you compile
// this file and link it with other files to produce an executable, this
// file does not by itself cause the resulting executable to be covered by
// the GNU General Public License.  This exception does not however
// invalidate any other reasons why the executable file might be covered by
// the GNU General Public License.

// Copyright (C) 2004 Ami Tavory and Vladimir Dreizin, IBM-HRL.

// Permission to use, copy, modify, sell, and distribute this software
// is hereby granted without fee, provided that the above copyright
// notice appears in all copies, and that both that copyright notice and
// this permission notice appear in supporting documentation. None of
// the above authors, nor IBM Haifa Research Laboratories, make any
// representation about the suitability of this software for any
// purpose. It is provided "as is" without express or implied warranty.

/**
 * @file bad_find_example.cpp
 * A basic example showing how *not* to use unordered containers.
 */

// For cc_hash_assoc_cntnr.
#include <ext/pb_assoc/assoc_cntnr.hpp>
// For pair.
#include <utility>

int
main()
{
  /*
   * A collision-chaining hash table mapping ints to chars.
   */
  typedef pb_assoc::cc_hash_assoc_cntnr< int, char> map_t;

  // An map_t object.
  map_t h;

  // Insert a value mapping the int 1 to the char 'a'.
  h.insert(std::make_pair(1, 'a'));

  /*
   * Find the entry of the key '1' the* wrong* way.
   * The following line will not compile, since map_t::find
   *	returns a find_iterator, which, by design, is not convertible
   *	to map_t::iterator.
   */
  map_t::iterator it = h.find(1); // { dg-error "conversion from" }
}