73ef4ff3
 Hu Chunming
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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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