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// -*- C++ -*-
// Copyright (C) 2013, Gabriel Dos Reis.
// All rights reserved.
// Written by Gabriel Dos Reis.
//
// Redistribution and use in source and binary forms, with or without
// modification, are permitted provided that the following conditions are
// met:
//
// - Redistributions of source code must retain the above copyright
// notice, this list of conditions and the following disclaimer.
//
// - Redistributions in binary form must reproduce the above copyright
// notice, this list of conditions and the following disclaimer in
// the documentation and/or other materials provided with the
// distribution.
//
// - Neither the name of OpenAxiom, nor the names of its contributors may
// be used to endorse or promote products derived from this software
// without specific prior written permission.
//
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
// IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
// TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
// PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
// OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
// EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
// PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
// LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
// NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
// SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#ifndef OPENAXIOM_DEFAULTS_included
#define OPENAXIOM_DEFAULTS_included
namespace OpenAxiom {
// -- The sole purpose of classes defines in this header is to
// -- provoke the automatic generation of definitions for functions
// -- defined within. These functions are not really friend. The
// -- friendship is such a mechanism to convince the C++ compiler
// -- to do something else. This is standard technique, also
// -- known as `based class parameterized by derived classes', or
// -- `curiously recurring pattern'.
namespace defaults {
// generate definition for != assuming existence of ==.
template<typename t>
struct neq {
friend bool operator!=(t x, t y) { return not(x == y); }
};
// generate definitions for ordering functions assuming <.
template<typename t>
struct ordering {
friend bool operator<=(t x, t y) { return not(y < x); }
friend bool operator>(t x, t y) { return y < x; }
friend bool operator>=(t x, t y) { return not(x < y); }
};
}
}
#endif // OPENAXIOM_DEFAULTS_included
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