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1 package gnu.kawa.brl;
2 import gnu.kawa.lispexpr.*;
3 import gnu.text.SyntaxException;
4 import gnu.mapping.*;
5 import gnu.text.SourceMessages;
6 import gnu.lists.*;
7
8
9
10 public class BRLRead extends LispReader
11 {
12 int nesting;
13
14
15 public boolean inLiteral ()
16 {
17 return ((InPort) port).readState == ']';
18 }
19
20 void init()
21 {
22 initialColonIsKeyword = false;
23 ((InPort) port).readState = ']';
24 }
25
26 public BRLRead(InPort port)
27 {
28 super(port);
29 init();
30 }
31
32 public BRLRead(InPort port, SourceMessages messages)
33 {
34 super(port, messages);
35 init();
36 }
37
38 public Object  readObject ()
39 throws java.io.IOException , SyntaxException
40 {
41 int startPos = tokenBufferLength;
42 InPort port = (InPort) getPort();
43 int saveNesting = nesting;
44 try
45 {
46 for (;;)
47 {
48 int ch = port.read();
49 if (ch < 0)
50 {
51 if (port.readState != ']' && ! isInteractive())
52 error('e', expressionStartFile,
53 expressionStartLine + 1, expressionStartColumn,
54 "an unmatched '[' was read");
55 return Sequence.eofValue; }
57 if (port.readState == ']')
58 {
59 port.unread();
60 Object value = BRL.brlReader.read(this, ']', 1);
61 if (ch == '[' && value == BRL.emptyForm)
62 continue;
63 return value;
64 }
65 else
66 {
67 if (ch == ']')
68 port.readState = ']';
69 else
70 {
71 nesting++;
72 Object value = readValues(ch, ReadTable.getCurrent());
73 if (value != Values.empty)
74 {
75 if (value == gnu.expr.QuoteExp.voidExp)
76 value = Values.empty;
77 return value;
78 }
79 nesting = saveNesting;
80 }
81 }
82 }
83 }
84 finally
85 {
86 nesting = saveNesting;
87 tokenBufferLength = startPos;
88 }
90 }
91
92 public static Object readObject(InPort port)
93 throws java.io.IOException , SyntaxException
94 {
95 return (new BRLRead(port)).readObject();
96 }
97
98 boolean brlCompatible = false;
99
100 public boolean isBrlCompatible() { return brlCompatible; }
101 public void setBrlCompatible(boolean compat)
102 {
103 brlCompatible = compat;
104 initialColonIsKeyword = compat;
105 }
106
107
108 String expressionStartFile;
109 int expressionStartLine;
110 int expressionStartColumn;
111
112 void saveExpressionStartPosition()
113 {
114 expressionStartFile = port.getName();
115 expressionStartLine = port.getLineNumber();
116 expressionStartColumn = port.getColumnNumber();
117 }
118 }
119 |
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