1 /* This file is part of NIT ( http://www.nitlanguage.org ).
3 * Copyright 2008 Jean Privat <jean@pryen.org>
4 * Based on algorithms developped for ( http://www.sablecc.org/ ).
6 * Licensed under the Apache License, Version 2.0 (the "License");
7 * you may not use this file except in compliance with the License.
8 * You may obtain a copy of the License at
10 * http://www.apache.org/licenses/LICENSE-2.0
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
19 $ template make_abs_nodes()
20 # Root of the AST hierarchy
22 readable var _location: nullable Location
25 # Ancestor of all tokens
30 # Ancestor of all productions
36 $ template make_nodes()
38 # Parent of the node in the AST
39 readable writable var _parent: nullable PNode
41 # Remove a child from the AST
42 fun remove_child(child: PNode)
44 replace_child(child, null)
47 # Replace a child with an other node in the AST
48 fun replace_child(old_child: PNode, new_child: nullable PNode) is abstract
50 # Replace itself with an other node in the AST
51 fun replace_with(node: PNode)
53 if (_parent != null) then
54 _parent.replace_child(self, node)
58 # Visit all nodes in order.
59 # Thus, call "v.visit(e)" for each node e
60 fun visit_all(v: Visitor) is abstract
62 # Visit all nodes in reverse order.
63 # Thus, call "v.visit(e)" for each node e starting from the last child
64 fun visit_all_reverse(v: Visitor) is abstract
66 # Give a human readable location of the node.
69 if location == null then
76 # Return only the line number of the node
77 fun line_number: Int is abstract
79 # Debug method: output a message prefixed with the location.
80 fun printl(str: String)
82 print("{locate}: {str}\n")
87 redef fun visit_all(v: Visitor) do end
88 redef fun visit_all_reverse(v: Visitor) do end
89 redef fun replace_child(old_child: PNode, new_child: nullable PNode) do end
91 redef fun line_number do return line
95 # The first token of the production node
96 readable writable var _first_token: nullable Token
98 # The last token of the production node
99 readable writable var _last_token: nullable Token
101 redef fun replace_with(n: PNode)
105 n.first_token = first_token
106 n.last_token = last_token
107 n._location = location
110 redef fun line_number
112 if first_token != null then
113 return first_token.line
120 # Abstract standard visitor
122 # Ask the visitor to visit a given node.
123 # Usually automatically called by visit_all* methods.
124 # Concrete visitors should redefine this method.
125 fun visit(e: nullable PNode) is abstract