79 lines
2.0 KiB
C++
79 lines
2.0 KiB
C++
// Copyright (C) 2016-2018 T. Zachary Laine
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//
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// Distributed under the Boost Software License, Version 1.0. (See
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// accompanying file LICENSE_1_0.txt or copy at
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// http://www.boost.org/LICENSE_1_0.txt)
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#include <boost/yap/yap.hpp>
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#include <boost/mpl/assert.hpp>
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#include <boost/test/minimal.hpp>
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#include <sstream>
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template<typename T>
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using term = boost::yap::terminal<boost::yap::minimal_expr, T>;
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namespace yap = boost::yap;
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namespace bh = boost::hana;
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struct iota_terminal_transform
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{
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template<typename T>
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auto operator()(boost::yap::expr_tag<boost::yap::expr_kind::terminal>, T && t)
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{
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return boost::yap::make_terminal(index_++);
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}
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template<typename CallableExpr, typename... Arg>
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auto operator()(boost::yap::expr_tag<boost::yap::expr_kind::call>,
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CallableExpr callable, Arg &&... arg)
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{
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return boost::yap::make_expression<boost::yap::expr_kind::call>(
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callable, boost::yap::transform(arg, *this)...);
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}
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int index_;
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};
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struct plus_expr_t
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{
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static yap::expr_kind const kind = yap::expr_kind::plus;
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bh::tuple<term<int>, term<int>> elements;
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};
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int test_main(int, char * [])
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{
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// Each node instantiated from from yap::expression.
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{
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auto plus_expr = yap::terminal<yap::expression, int>{{5}} + 6;
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BOOST_CHECK(yap::evaluate(plus_expr) == 11);
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BOOST_CHECK(
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yap::evaluate(
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yap::transform(plus_expr, iota_terminal_transform{0})) == 1);
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}
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// Each node instantiated from from yap::minimal_expr.
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{
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yap::minimal_expr<yap::expr_kind::plus, bh::tuple<term<int>, term<int>>>
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plus_expr;
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yap::evaluate(yap::transform(plus_expr, iota_terminal_transform{0}), 1);
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}
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// Leaves are instantiated from from yap::minimal_expr; nonterminal
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// expr_kind::plus does not even come from a template.
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{
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plus_expr_t plus_expr;
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yap::evaluate(yap::transform(plus_expr, iota_terminal_transform{0}), 1);
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}
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return 0;
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}
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