Mercurial Hosting > luan

comparison src/goodjava/parser/Parser.java @ 1402:27efb1fcbcb5

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
move luan.lib to goodjava
author Franklin Schmidt <fschmidt@gmail.com>
date Tue, 17 Sep 2019 01:35:01 -0400
parents src/luan/lib/parser/Parser.java@220228bf1af9
children
comparison
equal deleted inserted replaced
1401:ef1620aa99cb 1402:27efb1fcbcb5
1 package goodjava.parser;
2
3
4 public class Parser {
5 public final String text;
6 private final int len;
7 private int[] stack = new int[256];
8 private int frame = 0;
9 private int iHigh;
10
11 public Parser(String text) {
12 this.text = text;
13 this.len = text.length();
14 }
15
16 private int i() {
17 return stack[frame];
18 }
19
20 private void i(int i) {
21 stack[frame] += i;
22 if( iHigh < stack[frame] )
23 iHigh = stack[frame];
24 }
25
26 public int begin() {
27 frame++;
28 if( frame == stack.length ) {
29 int[] a = new int[2*frame];
30 System.arraycopy(stack,0,a,0,frame);
31 stack = a;
32 }
33 stack[frame] = stack[frame-1];
34 return i();
35 }
36
37 public void rollback() {
38 stack[frame] = frame==0 ? 0 : stack[frame-1];
39 }
40
41 public <T> T success(T t) {
42 success();
43 return t;
44 }
45
46 public boolean success() {
47 frame--;
48 stack[frame] = stack[frame+1];
49 return true;
50 }
51
52 public <T> T failure(T t) {
53 failure();
54 return t;
55 }
56
57 public boolean failure() {
58 frame--;
59 return false;
60 }
61
62 public int currentIndex() {
63 return i();
64 }
65 /*
66 public int errorIndex() {
67 return frame > 0 ? stack[frame-1] : 0;
68 }
69 */
70 public int highIndex() {
71 return iHigh;
72 }
73
74 public char lastChar() {
75 return text.charAt(i()-1);
76 }
77
78 public char currentChar() {
79 return text.charAt(i());
80 }
81
82 public boolean endOfInput() {
83 return i() >= len;
84 }
85
86 public boolean match(char c) {
87 if( endOfInput() || text.charAt(i()) != c )
88 return false;
89 i(1);
90 return true;
91 }
92
93 public boolean match(String s) {
94 int n = s.length();
95 if( !text.regionMatches(i(),s,0,n) )
96 return false;
97 i(n);
98 return true;
99 }
100
101 public boolean matchIgnoreCase(String s) {
102 int n = s.length();
103 if( !text.regionMatches(true,i(),s,0,n) )
104 return false;
105 i(n);
106 return true;
107 }
108
109 public boolean anyOf(String s) {
110 if( endOfInput() || s.indexOf(text.charAt(i())) == -1 )
111 return false;
112 i(1);
113 return true;
114 }
115
116 public boolean noneOf(String s) {
117 if( endOfInput() || s.indexOf(text.charAt(i())) != -1 )
118 return false;
119 i(1);
120 return true;
121 }
122
123 public boolean inCharRange(char cLow, char cHigh) {
124 if( endOfInput() )
125 return false;
126 char c = text.charAt(i());
127 if( !(cLow <= c && c <= cHigh) )
128 return false;
129 i(1);
130 return true;
131 }
132
133 public boolean anyChar() {
134 if( endOfInput() )
135 return false;
136 i(1);
137 return true;
138 }
139
140 public boolean test(char c) {
141 return !endOfInput() && text.charAt(i()) == c;
142 }
143
144 public boolean test(String s) {
145 return text.regionMatches(i(),s,0,s.length());
146 }
147
148 public boolean testIgnoreCase(String s) {
149 return text.regionMatches(true,i(),s,0,s.length());
150 }
151
152 public String textFrom(int start) {
153 return text.substring(start,i());
154 }
155
156 }