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comparison src/luan/interp/LuaParser.java @ 5:9ef0fd711101

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start LuaParser git-svn-id: https://luan-java.googlecode.com/svn/trunk@6 21e917c8-12df-6dd8-5cb6-c86387c605b9
author fschmidt@gmail.com <fschmidt@gmail.com@21e917c8-12df-6dd8-5cb6-c86387c605b9>
date Mon, 19 Nov 2012 09:49:06 +0000
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children a315783c9524
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4:24fd6381caca 5:9ef0fd711101
1 package luan.interp;
2
3 import java.util.Scanner;
4 import org.parboiled.BaseParser;
5 import org.parboiled.Parboiled;
6 import org.parboiled.Rule;
7 import org.parboiled.parserunners.ReportingParseRunner;
8 import org.parboiled.support.ParsingResult;
9 import org.parboiled.errors.ErrorUtils;
10 import luan.Lua;
11 import luan.LuaState;
12
13
14 public class LuaParser extends BaseParser<Object> {
15
16 public Rule Target() {
17 return Sequence(ConstExpr(), EOI);
18 }
19
20 public Rule ConstExpr() {
21 return Sequence(
22 Const(),
23 push(new ConstExpr(pop()))
24 );
25 }
26
27 public Rule Const() {
28 return FirstOf(
29 NilConst(),
30 BinaryConst(),
31 NumberConst()
32 );
33 }
34
35 public Rule NilConst() {
36 return Sequence(
37 String("nil"),
38 push(null)
39 );
40 }
41
42 public Rule BinaryConst() {
43 return FirstOf(
44 TrueConst(),
45 FalseConst()
46 );
47 }
48
49 public Rule TrueConst() {
50 return Sequence(
51 String("true"),
52 push(true)
53 );
54 }
55
56 public Rule FalseConst() {
57 return Sequence(
58 String("false"),
59 push(false)
60 );
61 }
62
63 public Rule NumberConst() {
64 return Sequence(
65 Number(),
66 push(Double.parseDouble(match()))
67 );
68 }
69
70 public Rule Number() {
71 return FirstOf(
72 Sequence(
73 Int(),
74 Optional(
75 Ch('.'),
76 Optional(Int())
77 ),
78 NumberExp()
79 ),
80 Sequence(
81 Ch('.'),
82 Int(),
83 NumberExp()
84 )
85 );
86 }
87
88 public Rule NumberExp() {
89 return Optional(
90 IgnoreCase('e'),
91 Optional(AnyOf("+-")),
92 Int()
93 );
94 }
95
96 Rule Int() {
97 return OneOrMore(Digit());
98 }
99
100 Rule Digit() {
101 return CharRange('0', '9');
102 }
103
104 // for testing
105 public static void main(String[] args) throws Exception {
106 LuaParser parser = Parboiled.createParser(LuaParser.class);
107 while( true ) {
108 String input = new Scanner(System.in).nextLine();
109 ParsingResult<?> result = new ReportingParseRunner(parser.Target()).run(input);
110 if( result.hasErrors() ) {
111 System.out.println("Parse Errors:\n" + ErrorUtils.printParseErrors(result));
112 } else {
113 Expr expr = (Expr)result.resultValue;
114 LuaState lua = new LuaState();
115 Object val = expr.eval(lua);
116 System.out.println("Result: "+Lua.toString(val));
117 }
118 }
119 }
120 }