1// sequence_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_SEQUENCE_NODE_HPP
7#define BOOST_SPIRIT_SUPPORT_DETAIL_LEXER_PARSER_TREE_SEQUENCE_NODE_HPP
8
9#include "node.hpp"
10
11namespace boost
12{
13namespace lexer
14{
15namespace detail
16{
17class sequence_node : public node
18{
19public:
20 sequence_node (node *left_, node *right_) :
21 node (left_->nullable () && right_->nullable ()),
22 _left (left_),
23 _right (right_)
24 {
25 _left->append_firstpos (firstpos_&: _firstpos);
26
27 if (_left->nullable ())
28 {
29 _right->append_firstpos (firstpos_&: _firstpos);
30 }
31
32 if (_right->nullable ())
33 {
34 _left->append_lastpos (lastpos_&: _lastpos);
35 }
36
37 _right->append_lastpos (lastpos_&: _lastpos);
38
39 node_vector &lastpos_ = _left->lastpos ();
40 const node_vector &firstpos_ = _right->firstpos ();
41
42 for (node_vector::iterator iter_ = lastpos_.begin (),
43 end_ = lastpos_.end (); iter_ != end_; ++iter_)
44 {
45 (*iter_)->append_followpos (firstpos_);
46 }
47 }
48
49 virtual ~sequence_node ()
50 {
51 }
52
53 virtual type what_type () const
54 {
55 return SEQUENCE;
56 }
57
58 virtual bool traverse (const_node_stack &node_stack_,
59 bool_stack &perform_op_stack_) const
60 {
61 perform_op_stack_.push (x: true);
62
63 switch (_right->what_type ())
64 {
65 case SEQUENCE:
66 case SELECTION:
67 case ITERATION:
68 perform_op_stack_.push (x: false);
69 break;
70 default:
71 break;
72 }
73
74 node_stack_.push (x: _right);
75 node_stack_.push (x: _left);
76 return true;
77 }
78
79private:
80 // Not owner of these pointers...
81 node *_left;
82 node *_right;
83
84 virtual void copy_node (node_ptr_vector &node_ptr_vector_,
85 node_stack &new_node_stack_, bool_stack &perform_op_stack_,
86 bool &down_) const
87 {
88 if (perform_op_stack_.top ())
89 {
90 node *rhs_ = new_node_stack_.top ();
91
92 new_node_stack_.pop ();
93
94 node *lhs_ = new_node_stack_.top ();
95
96 node_ptr_vector_->push_back (x: static_cast<sequence_node *>(0));
97 node_ptr_vector_->back () = new sequence_node (lhs_, rhs_);
98 new_node_stack_.top () = node_ptr_vector_->back ();
99 }
100 else
101 {
102 down_ = true;
103 }
104
105 perform_op_stack_.pop ();
106 }
107};
108}
109}
110}
111
112#endif
113

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