977ed18d
 Hu Chunming
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[/
Copyright (c) Vladimir Batov 2009-2022
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::cnv::range]
['boost::cnv::range] is a consolidation of the [begin, end)-based ranges (such as ['std::string]) and the sentry-based ranges (such as null-terminated C-style strings). It allows universal traversal of both types of ranges with
for (auto s = range.begin(); s != range.sentry(); ++s)
without the penalty or the need for an extra traversal of the sentry-based ranges in order to find the end.
TODO
[endsect]
[section boost::cnv::is_range]
TODO
[endsect]
[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 functionality 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]
[endsect]
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