[/
  Copyright (c) Vladimir Batov 2009-2014
  Distributed under the Boost Software License, Version 1.0.
  See copy at http://www.boost.org/LICENSE_1_0.txt.
]

[section:supporting_tools Supporting Tools]

This section describes a few supporting tools written as part of ['Boost.Convert] but which might be useful in their own rights.

[section BOOST_DECLARE_HAS_MEMBER]

The BOOST_DECLARE_HAS_MEMBER macro allows to declare a trait which would then let introspect the existence of a class member (a data member or a member function) with the specified name. 

For example, the following declarations introduce `local::has_begin` and `local::has_funop` traits which then allow to test if the supplied class has respectively `begin` and `operator()` members:

[has_member_declaration]

Now these traits can be used as follows:

[has_member_classes_tested]
[has_member_usage]

As it can be seen from the example the traits only check for the existence of a member (be that a data member or a member function) with the specified name. 

[endsect]
[section BOOST_DECLARE_IS_CALLABLE]

The BOOST_DECLARE_IS_CALLABLE macro extends the functonality provided by BOOST_DECLARE_HAS_MEMBER and allows to declare a trait which would then let introspect the existence of a named class member function ['callable with the supplied signature]. 

For example, the following declarations introduce `local::can_call_funop` and `local::can_call_func` traits: 

[is_callable_declaration]

The traits allow to test if the supplied class has respectively `operator()` and `func()` member functions callable with the specified signature:

[is_callable_classes_tested]
[is_callable_usage1]
[is_callable_usage2]

As it can be seen from the example the traits check for the existence of a ['callable] member function but ['not necessarily of the specified signature]. Please check the ['Boost.TTI] library for the latter.

[endsect]
[section `boost::cnv::is_cnv`]

TODO

[endsect]
[endsect]