Mercurial Hosting > luan

comparison src/luan/impl/Parser.java @ 775:1a68fc55a80c

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
simplify dir structure
author Franklin Schmidt <fschmidt@gmail.com>
date Fri, 26 Aug 2016 14:36:40 -0600
parents core/src/luan/impl/Parser.java@b620b8e1010f
children
comparison
equal deleted inserted replaced
774:3e30cf310e56 775:1a68fc55a80c
1 package luan.impl;
2
3
4 final class Parser {
5
6 private static class Frame {
7 int i;
8 StringBuilder sb;
9 }
10
11 // private final LuanSource src;
12 public final String text;
13 public final String sourceName;
14 private final int len;
15 private Frame[] stack = new Frame[256];
16 private int frame = 0;
17 private int iHigh;
18
19 public Parser(String text,String sourceName) {
20 // this.src = src;
21 this.text = text;
22 this.sourceName = sourceName;
23 this.len = text.length();
24 stack[0] = new Frame();
25 }
26
27 private int i() {
28 return stack[frame].i;
29 }
30
31 private void i(int i) {
32 Frame f = stack[frame];
33 f.i += i;
34 if( iHigh < f.i )
35 iHigh = f.i;
36 }
37
38 public int begin() {
39 frame++;
40 if( frame == stack.length ) {
41 Frame[] a = new Frame[2*frame];
42 System.arraycopy(stack,0,a,0,frame);
43 stack = a;
44 }
45 Frame f = new Frame();
46 f.i = stack[frame-1].i;
47 stack[frame] = f;
48 return i();
49 }
50
51 public void rollback() {
52 Frame f = stack[frame];
53 f.i = stack[frame-1].i;
54 f.sb = null;
55 }
56
57 public <T> T success(T t) {
58 success();
59 return t;
60 }
61
62 public boolean success() {
63 Frame f = stack[frame];
64 if( f.sb != null && f.sb.length() > 0 ) throw new RuntimeException("sb not emtpy");
65 frame--;
66 stack[frame].i = f.i;
67 return true;
68 }
69
70 public <T> T failure(T t) {
71 failure();
72 return t;
73 }
74
75 public boolean failure() {
76 frame--;
77 return false;
78 }
79
80 public ParseException exception(String msg) {
81 return new ParseException(msg,text,sourceName,i(),iHigh);
82 }
83
84 public ParseException exception() {
85 return exception("Invalid input");
86 }
87
88 public StringBuilder sb() {
89 Frame f = stack[frame];
90 if( f.sb == null )
91 f.sb = new StringBuilder();
92 return f.sb;
93 }
94
95 public void upSb() {
96 Frame f = stack[frame];
97 StringBuilder sb = f.sb;
98 if( sb != null && sb.length() > 0 ) {
99 Frame fUp = stack[frame-1];
100 if( fUp.sb == null )
101 fUp.sb = sb;
102 else
103 fUp.sb.append(sb.toString());
104 f.sb = null;
105 }
106 }
107
108 public int currentIndex() {
109 return i();
110 }
111
112 public char lastChar() {
113 return text.charAt(i()-1);
114 }
115
116 public char currentChar() {
117 return text.charAt(i());
118 }
119
120 public boolean endOfInput() {
121 return i() >= len;
122 }
123
124 public boolean match(char c) {
125 if( endOfInput() || text.charAt(i()) != c )
126 return false;
127 i(1);
128 return true;
129 }
130
131 public boolean match(String s) {
132 int n = s.length();
133 if( !text.regionMatches(i(),s,0,n) )
134 return false;
135 i(n);
136 return true;
137 }
138
139 public boolean matchIgnoreCase(String s) {
140 int n = s.length();
141 if( !text.regionMatches(true,i(),s,0,n) )
142 return false;
143 i(n);
144 return true;
145 }
146
147 public boolean anyOf(String s) {
148 if( endOfInput() || s.indexOf(text.charAt(i())) == -1 )
149 return false;
150 i(1);
151 return true;
152 }
153
154 public boolean noneOf(String s) {
155 if( endOfInput() || s.indexOf(text.charAt(i())) != -1 )
156 return false;
157 i(1);
158 return true;
159 }
160
161 public boolean inCharRange(char cLow, char cHigh) {
162 if( endOfInput() )
163 return false;
164 char c = text.charAt(i());
165 if( !(cLow <= c && c <= cHigh) )
166 return false;
167 i(1);
168 return true;
169 }
170
171 public boolean anyChar() {
172 if( endOfInput() )
173 return false;
174 i(1);
175 return true;
176 }
177
178 public boolean test(char c) {
179 return !endOfInput() && text.charAt(i()) == c;
180 }
181
182 public boolean test(String s) {
183 return text.regionMatches(i(),s,0,s.length());
184 }
185
186 public String textFrom(int start) {
187 return text.substring(start,i());
188 }
189
190 }