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The header <boost/assert.hpp> defines the macro BOOST_ASSERT, which is similar to the standard assert macro defined in <cassert>. The macro is intended to be used in Boost libraries.

By default, BOOST_ASSERT(expr) is equivalent to assert(expr).

When the macro BOOST_DISABLE_ASSERTS is defined when <boost/assert.hpp> is included, BOOST_ASSERT(expr) is defined as ((void)0). This allows users to selectively disable BOOST_ASSERT without affecting the definition of the standard assert.

When the macro BOOST_ENABLE_ASSERT_HANDLER is defined when <boost/assert.hpp> is included, BOOST_ASSERT(expr) evaluates expr and, if the result is false, evaluates the expression

::boost::assertion_failed(#expr, BOOST_CURRENT_FUNCTION, __FILE__, __LINE__)

assertion_failed is declared in <boost/assert.hpp> as

namespace boost

void assertion_failed(char const * expr, char const * function, char const * file, long line);


but it is never defined. The user is expected to supply an appropriate definition.

As is the case with <cassert>, <boost/assert.hpp> can be included multiple times in a single translation unit. BOOST_ASSERT will be redefined each time as specified above.

Copyright 2002 by Peter Dimov. Distributed under the Boost Software License, Version 1.0. See accompanying file LICENSE_1_0.txt or copy at