1 // Copyright (C) 2016-2018 T. Zachary Laine
2 //
3 // Distributed under the Boost Software License, Version 1.0. (See
4 // accompanying file LICENSE_1_0.txt or copy at
5 // http://www.boost.org/LICENSE_1_0.txt)
6 #include <boost/yap/yap.hpp>
7
8 #include <boost/mpl/assert.hpp>
9
10 #include <boost/test/minimal.hpp>
11
12 #include <sstream>
13
14
15 template<typename T>
16 using term = boost::yap::terminal<boost::yap::minimal_expr, T>;
17
18 namespace yap = boost::yap;
19 namespace bh = boost::hana;
20
21
22 struct iota_terminal_transform
23 {
24 template<typename T>
operator ()iota_terminal_transform25 auto operator()(boost::yap::expr_tag<boost::yap::expr_kind::terminal>, T && t)
26 {
27 return boost::yap::make_terminal(index_++);
28 }
29
30 template<typename CallableExpr, typename... Arg>
operator ()iota_terminal_transform31 auto operator()(boost::yap::expr_tag<boost::yap::expr_kind::call>,
32 CallableExpr callable, Arg &&... arg)
33 {
34 return boost::yap::make_expression<boost::yap::expr_kind::call>(
35 callable, boost::yap::transform(arg, *this)...);
36 }
37
38 int index_;
39 };
40
41 struct plus_expr_t
42 {
43 static yap::expr_kind const kind = yap::expr_kind::plus;
44
45 bh::tuple<term<int>, term<int>> elements;
46 };
47
test_main(int,char * [])48 int test_main(int, char * [])
49 {
50 // Each node instantiated from from yap::expression.
51 {
52 auto plus_expr = yap::terminal<yap::expression, int>{{5}} + 6;
53
54 BOOST_CHECK(yap::evaluate(plus_expr) == 11);
55
56 BOOST_CHECK(
57 yap::evaluate(
58 yap::transform(plus_expr, iota_terminal_transform{0})) == 1);
59 }
60
61 // Each node instantiated from from yap::minimal_expr.
62 {
63 yap::minimal_expr<yap::expr_kind::plus, bh::tuple<term<int>, term<int>>>
64 plus_expr;
65
66 yap::evaluate(yap::transform(plus_expr, iota_terminal_transform{0}), 1);
67 }
68
69 // Leaves are instantiated from from yap::minimal_expr; nonterminal
70 // expr_kind::plus does not even come from a template.
71 {
72 plus_expr_t plus_expr;
73
74 yap::evaluate(yap::transform(plus_expr, iota_terminal_transform{0}), 1);
75 }
76
77 return 0;
78 }
79