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1
3 package org.python.compiler;
4
5 import org.python.parser.*;
6 import org.python.parser.ast.*;
7 import java.util.*;
8
9 public class ScopesCompiler extends Visitor implements ScopeConstants {
10
11 private CompilationContext code_compiler;
12
13 private Stack scopes;
14 private ScopeInfo cur = null;
15 private Hashtable nodeScopes;
16
17 private int level = 0;
18 private int func_level = 0;
19
20 public ScopesCompiler(CompilationContext code_compiler,
21 Hashtable nodeScopes)
22 {
23 this.code_compiler = code_compiler;
24 this.nodeScopes = nodeScopes;
25 scopes = new Stack();
26 }
27
28 public void beginScope(String  name, int kind, SimpleNode node,
29 ArgListCompiler ac)
30 {
31 if (cur != null) {
32 scopes.push(cur);
33 }
34 if (kind == FUNCSCOPE) func_level++;
35 cur = new ScopeInfo(name, node, level++, kind,
36 func_level, ac);
37 nodeScopes.put(node, cur);
38 }
39
40 public void endScope() throws Exception {
41 if (cur.kind == FUNCSCOPE) func_level--;
42 level--;
43 ScopeInfo up = (!scopes.empty())?(ScopeInfo)scopes.pop():null;
44 cur.cook(up,code_compiler);
45 cur.dump(); cur = up;
47 }
48
49 public void parse(SimpleNode node) throws Exception {
50 try {
51 visit(node);
52 } catch(Throwable t) {
53 throw org.python.core.parser.fixParseError(null, t,
54 code_compiler.getFilename());
55 }
56 }
57
58 public Object visitInteractive(Interactive node) throws Exception {
59 beginScope("<single-top>", TOPSCOPE, node, null);
60 suite(node.body);
61 endScope();
62 return null;
63 }
64
65 public Object visitModule(org.python.parser.ast.Module node)
66 throws Exception
67 {
68 beginScope("<file-top>", TOPSCOPE, node, null);
69 suite(node.body);
70 endScope();
71 return null;
72 }
73
74 public Object visitExpression(Expression node) throws Exception {
75 beginScope("<eval-top>", TOPSCOPE, node, null);
76 visit(new Return(node.body));
77 endScope();
78 return null;
79 }
80
81 private void def(String name) {
82 cur.addBound(name);
83 }
84
85 public Object visitFunctionDef(FunctionDef node) throws Exception {
86 def(node.name);
87 ArgListCompiler ac = new ArgListCompiler();
88 ac.visitArgs(node.args);
89
90 exprType[] defaults = ac.getDefaults();
91 int defc = defaults.length;
92 for (int i = 0; i < defc; i++) {
93 visit(defaults[i]);
94 }
95
96 beginScope(node.name, FUNCSCOPE, node, ac);
97 int n = ac.names.size();
98 for (int i = 0; i < n; i++) {
99 cur.addParam((String )ac.names.elementAt(i));
100 }
101 for (int i = 0; i < ac.init_code.size(); i++) {
102 visit((stmtType) ac.init_code.elementAt(i));
103 }
104 cur.markFromParam();
105 suite(node.body);
106 endScope();
107 return null;
108 }
109
110 public Object visitLambda(Lambda node) throws Exception {
111 ArgListCompiler ac = new ArgListCompiler();
112 ac.visitArgs(node.args);
113
114 SimpleNode[] defaults = ac.getDefaults();
115 int defc = defaults.length;
116 for (int i = 0; i < defc; i++) {
117 visit(defaults[i]);
118 }
119
120 beginScope("<lambda>", FUNCSCOPE, node, ac);
121 int n = ac.names.size();
122 for (int i = 0; i < n; i++) {
123 cur.addParam((String )ac.names.elementAt(i));
124 }
125 for (int i = 0; i < ac.init_code.size(); i++)
126 visit((stmtType) ac.init_code.elementAt(i));
127 cur.markFromParam();
128 visit(node.body);
129 endScope();
130 return null;
131 }
132
133 public void suite(stmtType[] stmts) throws Exception {
134 int n = stmts.length;
135 for (int i = 0; i < n; i++)
136 visit(stmts[i]);
137 }
138
139 public Object visitImport(Import node) throws Exception {
140 int n = node.names.length;
141 for (int i = 0; i < n; i++) {
142 if (node.names[i].asname != null)
143 cur.addBound(node.names[i].asname);
144 else {
145 String name = node.names[i].name;
146 if (name.indexOf('.') > 0)
147 name = name.substring(0, name.indexOf('.'));
148 cur.addBound(name);
149 }
150 }
151 return null;
152 }
153
154 public Object visitImportFrom(ImportFrom node) throws Exception {
155 Future.checkFromFuture(node); int n = node.names.length;
157 if (n == 0) {
158 cur.from_import_star = true;
159 return null;
160 }
161 for (int i = 0; i < n; i++) {
162 if (node.names[i].asname != null)
163 cur.addBound(node.names[i].asname);
164 else
165 cur.addBound(node.names[i].name);
166 }
167 return null;
168 }
169
170 public Object visitGlobal(Global node) throws Exception {
171 int n = node.names.length;
172 for (int i = 0; i < n; i++) {
173 String name = node.names[i];
174 int prev = cur.addGlobal(name);
175 if (prev >= 0) {
176 if ((prev&FROM_PARAM) != 0)
177 code_compiler.error("name '"+name+"' is local and global",
178 true,node);
179 if ((prev&GLOBAL) != 0) continue;
180 String what;
181 if ((prev&BOUND) != 0) what = "assignment"; else what = "use";
182 code_compiler.error("name '"+name+"' declared global after "+
183 what,false,node);
184 }
185 }
186 return null;
187 }
188
189 public Object visitExec(Exec node) throws Exception {
190 cur.exec = true;
191 if (node.globals == null && node.locals == null)
192 cur.unqual_exec = true;
193 traverse(node);
194 return null;
195 }
196
197
208
209 public Object visitClassDef(ClassDef node) throws Exception {
210 def(node.name);
211 int n = node.bases.length;
212 for (int i = 0; i < n; i++)
213 visit(node.bases[i]);
214 beginScope(node.name, CLASSSCOPE, node, null);
215 suite(node.body);
216 endScope();
217 return null;
218 }
219
220 public Object visitName(Name node) throws Exception {
221 String name = node.id;
222 if (node.ctx != expr_contextType.Load) {
223 if (name.equals("__debug__"))
224 code_compiler.error("can not assign to __debug__", true,node);
225 cur.addBound(name);
226 }
227 else cur.addUsed(name);
228 return null;
229 }
230
231 public Object visitListComp(ListComp node) throws Exception {
232 String tmp = "_[" + (++cur.list_comprehension_count) + "]";
233 cur.addBound(tmp);
234 traverse(node);
235 return null;
236 }
237
238
239 public Object visitYield(Yield node) throws Exception {
240 cur.generator = true;
241 cur.yield_count++;
242 traverse(node);
243 return null;
244 }
245 }
246 |
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