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- [/
- Copyright (c) Vladimir Batov 2009-2016
- Distributed under the Boost Software License, Version 1.0.
- See copy at http://www.boost.org/LICENSE_1_0.txt.
- ]
- [section Alternative Interface]
- [:[*['"It's not a question of happiness, it's a requirement. Consider the alternative” Doug Horton]]]
- As it was indicated previously [@boost:/libs/optional/index.html `boost::optional`] is the actual type returned by the `boost::convert()` main interface:
- boost::optional<TypeOut> boost::convert(TypeIn const&, Converter const&);
- The signature is ['functionally-complete] and routinely elided during compilation. Still, the following alternative (and arguably more traditional) interface might be potentially more suitable for certain deployment scenarios (or due to personal preferences):
- TypeOut convert(TypeIn const&, Converter const&, TypeOut const& fallback_value);
- TypeOut convert(TypeIn const&, Converter const&, Functor const& fallback_func);
- TypeOut convert(TypeIn const&, Converter const&, boost::throw_on_failure);
- The interface still provides unambiguous behavior and readability, full support for various program flows and various degrees of conversion-failure detection and processing. It can be deployed in a similar fashion as follows:
- [getting_serious_example5]
- [getting_serious_example7]
- Still, the described interfaces are convenience wrappers around the main interface which provides the described behavior with:
- [getting_serious_example8]
- [endsect] [/section Return Value]
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