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
24 # Ancestor of all tokens
29 # Ancestor of all productions
35 $ template make_nodes()
37 # Parent of the node in the AST
38 readable writable var _parent: nullable PNode
40 # Remove a child from the AST
41 fun remove_child(child: PNode)
43 replace_child(child, null)
46 # Replace a child with an other node in the AST
47 fun replace_child(old_child: PNode, new_child: nullable PNode) is abstract
49 # Replace itself with an other node in the AST
50 fun replace_with(node: PNode)
52 if (_parent != null) then
53 _parent.replace_child(self, node)
57 # Visit all nodes in order.
58 # Thus, call "v.visit(e)" for each node e
59 fun visit_all(v: Visitor) is abstract
61 # Visit all nodes in reverse order.
62 # Thus, call "v.visit(e)" for each node e starting from the last child
63 fun visit_all_reverse(v: Visitor) is abstract
65 # Give a human readable location of the node.
66 fun locate: String is abstract
68 # Return only the line number of the node
69 fun line_number: Int is abstract
71 # Debug method: output a message prefixed with the location.
72 fun printl(str: String)
74 print("{locate}: {str}\n")
79 redef fun visit_all(v: Visitor) do end
80 redef fun visit_all_reverse(v: Visitor) do end
81 redef fun replace_child(old_child: PNode, new_child: nullable PNode) do end
83 redef fun locate: String
85 return "{filename}:{line},{pos}"
88 redef fun line_number do return line
92 # The first token of the production node
93 readable writable var _first_token: nullable Token
95 # The last token of the production node
96 readable writable var _last_token: nullable Token
98 redef fun locate: String
100 if first_token == null then
103 if last_token == null then
104 return "{first_token.locate}--????"
106 var lastpos = last_token.pos + last_token.text.length - 1
107 if first_token.line == last_token.line then
108 return "{first_token.locate}--{lastpos}"
110 return "{first_token.locate}--{last_token.line}:{lastpos}"
114 redef fun replace_with(n: PNode)
118 n.first_token = first_token
119 n.last_token = last_token
122 redef fun line_number
124 if first_token != null then
125 return first_token.line
132 # Abstract standard visitor
134 # Ask the visitor to visit a given node.
135 # Usually automatically called by visit_all* methods.
136 # Concrete visitors should redefine this method.
137 fun visit(e: nullable PNode) is abstract