1 // Copyright 2006 all rights reserved; see LICENSE file for BSD-style license
3 package edu.berkeley.sbp.tib;
4 import edu.berkeley.sbp.*;
5 import edu.berkeley.sbp.misc.*;
6 import edu.berkeley.sbp.chr.*;
11 * A slow, ugly, inefficient, inelegant, ad-hoc parser for TIB files.
13 * Despite being inelegant, this parser keeps all internal state on
14 * the stack (the only heap objects created are those which are
17 * This was written as an ad-hoc parser to facilitate
18 * experimentation with the TIB spec. Once the spec is finalized it
19 * should probably be rewritten.
21 public class Tib implements Input<Character> {
23 public String showRegion(Region<Character> r) { return ""; }
25 public Tib(String s) throws IOException { this(new StringReader(s)); }
26 public Tib(Reader r) throws IOException { this(new BufferedReader(r)); }
27 public Tib(InputStream is) throws IOException { this(new BufferedReader(new InputStreamReader(is))); }
28 public Tib(BufferedReader br) throws IOException {
32 //System.out.println("\rparsing: \"" + cur.toString(0, -1) + "\"");
34 public String getName() { return null; }
35 private String s = "";
42 public Input.Location getLocation() { return new Cartesian.Location(_col, _row, _scalar); }
43 private BufferedReader br;
45 char left = CharAtom.left;
46 char right = CharAtom.right;
48 boolean waiting = false;
49 char waitingChar = ' ';
50 boolean indenting = true;
52 private ArrayList<Integer> istack = new ArrayList<Integer>();
53 private static boolean debug = "true".equals(System.getProperty("tib.debug", "false"));
54 public Character next() throws IOException {
55 Character ret = nextc();
57 if (ret==null) return null;
58 else if (ret==left) System.out.print("\033[31m{\033[0m");
59 else if (ret==right) System.out.print("\033[31m}\033[0m");
60 else System.out.print(ret);
65 Character waitingBrace = null;
66 public Character nextc() throws IOException {
68 if (waitingBrace != null) {
69 Character ret = waitingBrace;
79 if (istack.size() > 1) {
80 istack.remove(istack.size()-1);
87 if (c=='\n') { _row++; _col=0; }
91 if (c==' ') { indentation++; return done(c); }
92 if (c=='\n') { indentation = 0; if (blank) return nextc(); blank = true; waiting = true; waitingChar='\n'; return '\n'; }
93 int last = istack.size()==0 ? -1 : istack.get(istack.size()-1);
94 if (indentation==last) {
101 //return nextc(numstates);
110 if (indentation > last) {
112 istack.add(indentation);
113 //System.out.print("\033[31m+"+indentation+"+\033[0m");
115 } else /*if (indentation < last)*/ {
116 istack.remove(istack.size()-1);
117 //System.out.print("\033[31m-"+last+"-\033[0m");
123 if (c=='\n') { indenting=true; indentation = 0; }
128 public Character done(char c) {
130 case '{': return left;
131 case '}': return right;
135 boolean blank = false;
137 // Grammar //////////////////////////////////////////////////////////////////////////////
140 public static class Grammar extends ReflectiveGrammar {
141 private int anon = 0;
142 private final Element ws = Sequence.maximal0(getNonTerminal("w"));
143 public Grammar(Class c) { super(c); dropAll.add(ws); }
144 public Object walk(Tree<String> tree) {
145 String head = tree.head();
146 if (tree.numChildren()==0) return super.walk(tree);
147 if ("{".equals(head)) {
148 Union u = new Union("???");
149 Union u2 = ((PreSequence)walk(tree, 0)).sparse(ws).buildUnion();
150 u2.add(Sequence.singleton(new Element[] { u }, 0));
151 return anonymousNonTerminal(new Sequence[][] {
153 Sequence.singleton(new Element[] { CharAtom.leftBrace,
162 return super.walk(tree);
168 public class Braces extends Union {
170 private static final Element left = string("{");
171 private static final Element right = string("}");
173 public static String join(Object[] e) {
174 StringBuffer ret = new StringBuffer();
175 for(int i=0; i<e.length; i++) {
176 if (i>0) ret.append(" ");
179 return ret.toString();
182 public Braces(Element[] e, Element sep) {
183 super("{"+join(e)+"}");
184 Element[] e2 = new Element[sep == null ? e.length+2 : e.length + 4];
186 e2[e2.length-1] = right;
189 e2[e2.length-2] = sep;
191 for(int i=0; i<e.length; i++) e2[i+(sep==null ? 1 : 2)] = e[i];
192 addAlternative(new Sequence.Singleton(e2));
193 addAlternative(new Sequence.Singleton(sep==null ? new Element[] { left, this, right} : new Element[] { left, sep, this, sep, right }));