35 lines
1.5 KiB
Plaintext
35 lines
1.5 KiB
Plaintext
[/
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Copyright (c) Vladimir Batov 2009-2016
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Distributed under the Boost Software License, Version 1.0.
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See copy at http://www.boost.org/LICENSE_1_0.txt.
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]
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[section Alternative Interface]
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[:[*['"It's not a question of happiness, it's a requirement. Consider the alternative” Doug Horton]]]
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As it was indicated previously [@boost:/libs/optional/index.html `boost::optional`] is the actual type returned by the `boost::convert()` main interface:
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boost::optional<TypeOut> boost::convert(TypeIn const&, Converter const&);
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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):
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TypeOut convert(TypeIn const&, Converter const&, TypeOut const& fallback_value);
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TypeOut convert(TypeIn const&, Converter const&, Functor const& fallback_func);
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TypeOut convert(TypeIn const&, Converter const&, boost::throw_on_failure);
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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:
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[getting_serious_example5]
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[getting_serious_example7]
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Still, the described interfaces are convenience wrappers around the main interface which provides the described behavior with:
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[getting_serious_example8]
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[endsect] [/section Return Value]
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