1// node.hpp
2// Copyright (c) 2007-2009 Ben Hanson (http://www.benhanson.net/)
3//
4// Distributed under the Boost Software License, Version 1.0. (See accompanying
5// file licence_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6#ifndef BOOST_SPIRIT_SUPPORT_DETAIL_LEXER_PARSER_TREE_NODE_HPP
7#define BOOST_SPIRIT_SUPPORT_DETAIL_LEXER_PARSER_TREE_NODE_HPP
8
9#include <boost/assert.hpp>
10#include "../../containers/ptr_vector.hpp"
11#include "../../runtime_error.hpp"
12#include "../../size_t.hpp"
13#include <stack>
14#include <vector>
15
16namespace boost
17{
18namespace lexer
19{
20namespace detail
21{
22class node
23{
24public:
25 enum type {LEAF, SEQUENCE, SELECTION, ITERATION, END};
26
27 typedef std::stack<bool> bool_stack;
28 typedef std::stack<node *> node_stack;
29 // stack and vector not owner of node pointers
30 typedef std::stack<const node *> const_node_stack;
31 typedef std::vector<node *> node_vector;
32 typedef ptr_vector<node> node_ptr_vector;
33
34 node () :
35 _nullable (false)
36 {
37 }
38
39 node (const bool nullable_) :
40 _nullable (nullable_)
41 {
42 }
43
44 virtual ~node ()
45 {
46 }
47
48 bool nullable () const
49 {
50 return _nullable;
51 }
52
53 void append_firstpos (node_vector &firstpos_) const
54 {
55 firstpos_.insert (position: firstpos_.end (),
56 first: _firstpos.begin (), last: _firstpos.end ());
57 }
58
59 void append_lastpos (node_vector &lastpos_) const
60 {
61 lastpos_.insert (position: lastpos_.end (),
62 first: _lastpos.begin (), last: _lastpos.end ());
63 }
64
65 virtual void append_followpos (const node_vector &/*followpos_*/)
66 {
67 throw runtime_error ("Internal error node::append_followpos()");
68 }
69
70 node *copy (node_ptr_vector &node_ptr_vector_) const
71 {
72 node *new_root_ = 0;
73 const_node_stack node_stack_;
74 bool_stack perform_op_stack_;
75 bool down_ = true;
76 node_stack new_node_stack_;
77
78 node_stack_.push (x: this);
79
80 while (!node_stack_.empty ())
81 {
82 while (down_)
83 {
84 down_ = node_stack_.top ()->traverse (node_stack_,
85 perform_op_stack_);
86 }
87
88 while (!down_ && !node_stack_.empty ())
89 {
90 const node *top_ = node_stack_.top ();
91
92 top_->copy_node (node_ptr_vector_, new_node_stack_,
93 perform_op_stack_, down_);
94
95 if (!down_) node_stack_.pop ();
96 }
97 }
98
99 BOOST_ASSERT(new_node_stack_.size () == 1);
100 new_root_ = new_node_stack_.top ();
101 new_node_stack_.pop ();
102 return new_root_;
103 }
104
105 virtual type what_type () const = 0;
106
107 virtual bool traverse (const_node_stack &node_stack_,
108 bool_stack &perform_op_stack_) const = 0;
109
110 node_vector &firstpos ()
111 {
112 return _firstpos;
113 }
114
115 const node_vector &firstpos () const
116 {
117 return _firstpos;
118 }
119
120 // _lastpos modified externally, so not const &
121 node_vector &lastpos ()
122 {
123 return _lastpos;
124 }
125
126 virtual bool end_state () const
127 {
128 return false;
129 }
130
131 virtual std::size_t id () const
132 {
133 throw runtime_error ("Internal error node::id()");
134 }
135
136 virtual std::size_t unique_id () const
137 {
138 throw runtime_error ("Internal error node::unique_id()");
139 }
140
141 virtual std::size_t lexer_state () const
142 {
143 throw runtime_error ("Internal error node::state()");
144 }
145
146 virtual std::size_t token () const
147 {
148 throw runtime_error ("Internal error node::token()");
149 }
150
151 virtual void greedy (const bool /*greedy_*/)
152 {
153 throw runtime_error ("Internal error node::token(bool)");
154 }
155
156 virtual bool greedy () const
157 {
158 throw runtime_error ("Internal error node::token()");
159 }
160
161 virtual const node_vector &followpos () const
162 {
163 throw runtime_error ("Internal error node::followpos()");
164 }
165
166 virtual node_vector &followpos ()
167 {
168 throw runtime_error ("Internal error node::followpos()");
169 }
170
171protected:
172 const bool _nullable;
173 node_vector _firstpos;
174 node_vector _lastpos;
175
176 virtual void copy_node (node_ptr_vector &node_ptr_vector_,
177 node_stack &new_node_stack_, bool_stack &perform_op_stack_,
178 bool &down_) const = 0;
179
180private:
181 node (node const &); // No copy construction.
182 node &operator = (node const &); // No assignment.
183};
184}
185}
186}
187
188#endif
189

source code of boost/libs/spirit/include/boost/spirit/home/support/detail/lexer/parser/tree/node.hpp