54 lines
1.0 KiB
Plaintext
54 lines
1.0 KiB
Plaintext
[#spaces]
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[section spaces]
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[h1 Synopsis]
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struct spaces;
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This is a [link parser parser].
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[h1 Description]
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`spaces` accepts any number of whitespace characters. It requires at least one
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to be present.
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[h1 Header]
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#include <boost/metaparse/spaces.hpp>
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[h1 Expression semantics]
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spaces
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is equivalent to
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repeated1<space>
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[h1 Example]
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#include <boost/metaparse/spaces.hpp>
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#include <boost/metaparse/start.hpp>
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#include <boost/metaparse/string.hpp>
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#include <boost/metaparse/is_error.hpp>
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#include <boost/metaparse/get_remaining.hpp>
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#include <type_traits>
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using namespace boost::metaparse;
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static_assert(
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std::is_same<
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BOOST_METAPARSE_STRING("foo"),
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get_remaining<spaces::apply<BOOST_METAPARSE_STRING(" foo"), start>>::type
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>::type::value,
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"it should consume all whitespaces at the beginning of the input"
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);
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static_assert(
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is_error<spaces::apply<BOOST_METAPARSE_STRING("x"), start>>::type::value,
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"it should return an error when the input does not begin with a whitespace"
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);
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[endsect]
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