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- [#repeated1]
- [section repeated1]
- [h1 Synopsis]
- template <class P>
- struct repeated1;
- This is a [link parser_combinator parser combinator].
- [table Arguments
- [[Name] [Type]]
- [[`P`] [[link parser parser]]]
- ]
- [h1 Description]
- It applies `P` on the input string repeatedly as long as the parser accepts the
- input. The result of parsing is a sequence of the results of the individual
- applications of `P`.
- When `P` rejects the input for the first time, `repeated1` rejects it as well.
- At least one successful application of `P` is required for `repeated1` to accept
- the input.
- [h1 Header]
- #include <boost/metaparse/repeated1.hpp>
- [h1 Expression semantics]
- For any `p` parser the following are equivalent:
- repeated1<p>
-
- last_of<look_ahead<p>, repeated<p>>
- [h1 Example]
- #include <boost/metaparse/repeated1.hpp>
- #include <boost/metaparse/digit_val.hpp>
- #include <boost/metaparse/start.hpp>
- #include <boost/metaparse/string.hpp>
- #include <boost/metaparse/get_result.hpp>
- #include <boost/metaparse/is_error.hpp>
-
- #include <boost/mpl/equal.hpp>
- #include <boost/mpl/vector.hpp>
- #include <boost/mpl/int.hpp>
-
- using namespace boost::metaparse;
-
- using digits = repeated1<digit_val>;
-
- static_assert(
- boost::mpl::equal<
- get_result<digits::apply<BOOST_METAPARSE_STRING("1234"), start>>::type,
- boost::mpl::vector<
- boost::mpl::int_<1>,
- boost::mpl::int_<2>,
- boost::mpl::int_<3>,
- boost::mpl::int_<4>
- >
- >::type::value,
- "the result of parsing should be the list of digit values"
- );
-
- static_assert(
- is_error<digits::apply<BOOST_METAPARSE_STRING("x"), start>>::type::value,
- "repeated1 should reject the input when it can't parse anything with digit_val"
- );
- [endsect]
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