57 lines
1.1 KiB
Plaintext
57 lines
1.1 KiB
Plaintext
[#get_message]
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[section get_message]
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[h1 Synopsis]
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template <class E>
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struct get_message;
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This is a [link lazy_metafunction lazy template metafunction].
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[table Arguments
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[[Name] [Type]]
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[[`E`] [[link reject reject] value]]
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]
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[h1 Description]
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Returns the error message of a parsing failure.
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[h1 Header]
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#include <boost/metaparse/get_message.hpp>
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[h1 Example]
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#include <boost/metaparse/get_message.hpp>
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#include <boost/metaparse/start.hpp>
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#include <boost/metaparse/reject.hpp>
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#include <boost/metaparse/define_error.hpp>
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#include <type_traits>
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using namespace boost::metaparse;
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BOOST_METAPARSE_DEFINE_ERROR(sample_error, "Sample error message");
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struct returns_reject
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{
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using type = reject<sample_error, start>;
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};
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static_assert(
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std::is_same<
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sample_error,
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get_message<reject<sample_error, start>>::type
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>::type::value,
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"It should return the message"
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);
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static_assert(
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std::is_same<sample_error, get_message<returns_reject>::type>::type::value,
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"It should support lazy evaluation"
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);
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[endsect]
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