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repeated_reject_incomplete1

Synopsis

template <class P>
struct repeated_reject_incomplete1;

This is a parser combinator.

Table 73. Arguments

Name

Type

P

parser


Description

The same as repeated1, but once P rejects the input, repeated_reject_incomplete1 checks if P consumes any characters before rejecting the input. If so, repeated_reject_incomplete1 rejects the input with the same error message this last application of P returned. Otherwise _reject_incompleterepeated1 accepts the input and gives the same result as repeated1.

Header

#include <boost/metaparse/repeated_reject_incomplete1.hpp>

Expression semantics

For any p parser, s compile-time string and pos source position

repeated_reject_incomplete1<p>::apply<s, pos>

is equivalent to

first_of<repeated1<p>, fail_at_first_char_expected<p> >::apply<s, pos>

Example

#include <boost/metaparse/repeated_reject_incomplete1.hpp>
#include <boost/metaparse/lit_c.hpp>
#include <boost/metaparse/last_of.hpp>
#include <boost/metaparse/token.hpp>
#include <boost/metaparse/int_.hpp>
#include <boost/metaparse/string.hpp>
#include <boost/metaparse/start.hpp>
#include <boost/metaparse/get_result.hpp>
#include <boost/metaparse/is_error.hpp>

#include <boost/mpl/equal.hpp>
#include <boost/mpl/vector_c.hpp>

using namespace boost::metaparse;

using int_token = token<int_>;
using plus_token = token<lit_c<'+'>>;
using plus_int = last_of<plus_token, int_token>;

using ints = repeated_reject_incomplete1<plus_int>;

static_assert(
  boost::mpl::equal<
    boost::mpl::vector_c<int, 13, 3, 21>,
    get_result<
      ints::apply<BOOST_METAPARSE_STRING("+ 13 + 3 + 21"), start>
    >::type
  >::type::value,
  "ints should parse the numbers"
);

static_assert(
  is_error<
    ints::apply<BOOST_METAPARSE_STRING("+ 13 + 3 +"), start>
  >::type::value,
  "when the last number is missing, it should be an error"
);

static_assert(
  is_error<ints::apply<BOOST_METAPARSE_STRING(""), start>>::type::value,
  "when no numbers are provided, it should be an error"
);

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