50 lines
1.2 KiB
C++
50 lines
1.2 KiB
C++
#ifndef BOOST_METAPARSE_GETTING_STARTED_7_HPP
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#define BOOST_METAPARSE_GETTING_STARTED_7_HPP
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// Automatically generated header file
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// Definitions before section 6.2
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#include "6_2.hpp"
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// Definitions of section 6.2
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#include <boost/mpl/minus.hpp>
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template <class L, char Op, class R> struct eval_binary_op;
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template <class L, class R> struct eval_binary_op<L, '+', R> : boost::mpl::plus<L, R>::type {};
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template <class L, class R> struct eval_binary_op<L, '-', R> : boost::mpl::minus<L, R>::type {};
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// query:
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// eval_binary_op<boost::mpl::int_<11>, '+', boost::mpl::int_<2>>::type
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// query:
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// eval_binary_op<boost::mpl::int_<13>, '-', boost::mpl::int_<2>>::type
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template <class S, class Item>
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struct binary_op :
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eval_binary_op<
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S,
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boost::mpl::at_c<Item, 0>::type::value,
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typename boost::mpl::at_c<Item, 1>::type
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>
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{};
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// query:
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// binary_op<boost::mpl::int_<11>, boost::mpl::vector<boost::mpl::char_<'+'>, boost::mpl::int_<2>>>::type
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using exp_parser13 =
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build_parser<
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foldl_start_with_parser<
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sequence<one_of<plus_token, minus_token>, int_token>,
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int_token,
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boost::mpl::quote2<binary_op>
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>
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>;
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// query:
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// exp_parser13::apply<BOOST_METAPARSE_STRING("1 + 2 - 3")>::type
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#endif
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