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1 package gnu.jemacs.lang;
2 import kawa.lang.*;
3 import gnu.lists.*;
4 import gnu.expr.*;
5 import gnu.mapping.Symbol;
6
7 public class defcustom extends Syntax
8 {
9 public boolean scanForDefinitions (Pair st, java.util.Vector  forms,
10 ScopeExp defs, Translator tr)
11 {
12 if (! (st.cdr instanceof Pair))
13 return super.scanForDefinitions(st, forms, defs, tr);
14 Pair p = (Pair) st.cdr;
15 Object name = p.car;
16 if (name instanceof String || name instanceof Symbol)
17 {
18 Declaration decl = defs.lookup(name);
19 if (decl == null)
20 {
21 decl = new Declaration(name);
22 defs.addDeclaration(decl);
23 }
24 else
25 tr.error('w', "duplicate declaration for `"+name+"'");
26 p = Translator.makePair(p, decl, p.cdr);
27 st = Translator.makePair(st, this, p);
28 if (defs instanceof ModuleExp)
29 {
30 decl.setCanRead(true);
31 decl.setCanWrite(true);
32 }
33 }
34 forms.addElement (st);
35 return true;
36 }
37
38 public Expression rewriteForm (Pair form, Translator tr)
39 {
40 Object obj = form.cdr;
41 String name = null;
42 Expression value = null;
43 Declaration decl = null;
44
45 if (obj instanceof Pair)
46 {
47 Pair p1 = (Pair) obj;
48 if (p1.car instanceof Declaration)
49 {
50 decl = (Declaration) p1.car;
51 name = decl.getName();
52 if (p1.cdr instanceof Pair)
53 {
54 Pair p2 = (Pair) p1.cdr;
55 value = tr.rewrite (p2.car);
56 if (p2.cdr != LList.Empty)
57 {
58 }
60 }
61 else if (p1.cdr != LList.Empty)
62 name = null;
63 }
64 }
65 if (name == null)
66 return tr.syntaxError ("invalid syntax for "+getName());
67 SetExp sexp = new SetExp (name, value);
68 sexp.setDefining (true);
69 if (decl != null)
70 {
71 sexp.setBinding(decl);
72 if (decl.context instanceof ModuleExp
73 && decl.getCanWrite())
74 value = null;
75 decl.noteValue(value);
76 }
77 return sexp;
78 }
79
80 }
81 |
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