| // (C) Copyright Jeremy Siek 1999. |
| // (C) Copyright David Abrahams 1999. |
| // (C) Copyright John Maddock 2001. |
| // Use, modification and distribution are subject to the |
| // Boost Software License, Version 1.0. (See accompanying file |
| // LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt) |
| |
| // See http://www.boost.org/libs/config for most recent version. |
| |
| // MACRO: BOOST_NO_OPERATORS_IN_NAMESPACE |
| // TITLE: friend operators in namespace |
| // DESCRIPTION: Compiler requires inherited operator |
| // friend functions to be defined at namespace scope, |
| // then using'ed to boost. |
| // Probably GCC specific. See boost/operators.hpp for example. |
| |
| namespace boost{ |
| |
| // |
| // the following is taken right out of <boost/operators.hpp> |
| // |
| template <class T> |
| struct addable1 |
| { |
| friend T operator+(T x, const T& y) { return x += y; } |
| friend bool operator != (const T& a, const T& b) { return !(a == b); } |
| }; |
| |
| struct spoiler1 |
| {}; |
| |
| spoiler1 operator+(const spoiler1&,const spoiler1&); |
| bool operator !=(const spoiler1&, const spoiler1&); |
| |
| |
| } // namespace boost |
| |
| namespace boost_no_operators_in_namespace{ |
| |
| struct spoiler2 |
| {}; |
| |
| spoiler2 operator+(const spoiler2&,const spoiler2&); |
| bool operator !=(const spoiler2&, const spoiler2&); |
| |
| |
| class add : public boost::addable1<add> |
| { |
| int val; |
| public: |
| add(int i) { val = i; } |
| add(const add& a){ val = a.val; } |
| add& operator+=(const add& a) { val += a.val; return *this; } |
| bool operator==(const add& a)const { return val == a.val; } |
| }; |
| |
| int test() |
| { |
| add a1(2); |
| add a2(3); |
| add a3(0); |
| a3 = a1 + a2; |
| bool b1 = (a1 == a2); |
| b1 = (a1 != a2); |
| (void)b1; |
| return 0; |
| } |
| |
| } |
| |
| |
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| |