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.*;
10 // TODO: multiple {{ }} for superquotation
15 * A slow, ugly, inefficient, inelegant, ad-hoc parser for TIB files.
17 * Despite being inelegant, this parser keeps all internal state on
18 * the stack (the only heap objects created are those which are
21 * This was written as an ad-hoc parser to facilitate
22 * experimentation with the TIB spec. Once the spec is finalized it
23 * should probably be rewritten.
25 public class Tib implements Input<Character> {
27 public String showRegion(Region<Character> r) { return null; }
29 public Tib(String s) throws IOException { this(new StringReader(s)); }
30 public Tib(Reader r) throws IOException { this(new BufferedReader(r)); }
31 public Tib(InputStream is) throws IOException { this(new BufferedReader(new InputStreamReader(is))); }
32 public Tib(BufferedReader br) throws IOException {
36 //System.out.println("\rparsing: \"" + cur.toString(0, -1) + "\"");
39 private String s = "";
46 public Input.Location getLocation() { return new Cartesian.Location(_col, _row, _scalar); }
47 private BufferedReader br;
49 char left = CharAtom.left;
50 char right = CharAtom.right;
52 boolean waiting = false;
53 char waitingChar = ' ';
54 boolean indenting = true;
56 private ArrayList<Integer> istack = new ArrayList<Integer>();
57 public Character next() throws IOException {
58 Character ret = nextc();
59 if (ret==null) return null;
60 else if (ret==left) System.out.print("\033[31m{\033[0m");
61 else if (ret==right) System.out.print("\033[31m}\033[0m");
62 else System.out.print(ret);
66 Character waitingBrace = null;
67 public Character nextc() throws IOException {
69 if (waitingBrace != null) {
70 Character ret = waitingBrace;
80 if (istack.size() > 1) {
81 istack.remove(istack.size()-1);
88 if (c=='\n') { _row++; _col=0; }
92 if (c==' ') { indentation++; return done(c); }
93 if (c=='\n') { indentation = 0; if (blank) return nextc(); blank = true; waiting = true; waitingChar='\n'; return '\n'; }
94 int last = istack.size()==0 ? -1 : istack.get(istack.size()-1);
95 if (indentation==last) {
102 //return nextc(numstates);
111 if (indentation > last) {
113 istack.add(indentation);
114 //System.out.print("\033[31m+"+indentation+"+\033[0m");
116 } else /*if (indentation < last)*/ {
117 istack.remove(istack.size()-1);
118 //System.out.print("\033[31m-"+last+"-\033[0m");
124 if (c=='\n') { indenting=true; indentation = 0; }
129 public Character done(char c) {
131 case '{': return left;
132 case '}': return right;
136 boolean blank = false;
138 // Grammar //////////////////////////////////////////////////////////////////////////////
141 public static class Grammar extends ReflectiveGrammar {
142 private int anon = 0;
143 private final Element ws = Sequence.maximal0(getNonTerminal("w"));
144 public Grammar(Class c) { super(c); dropAll.add(ws); }
145 public Object walk(Tree<String> tree) {
146 String head = tree.head();
147 if (tree.numChildren()==0) return super.walk(tree);
148 if ("{".equals(head)) {
149 Union u = new Union("???");
150 Union u2 = ((PreSequence)walk(tree, 0)).sparse(ws).buildUnion();
151 u2.add(Sequence.singleton(new Element[] { u }, 0));
152 return anonymousNonTerminal(new Sequence[][] {
154 Sequence.singleton(new Element[] { CharAtom.leftBrace,
163 return super.walk(tree);
169 public class Braces extends Union {
171 private static final Element left = string("{");
172 private static final Element right = string("}");
174 public static String join(Object[] e) {
175 StringBuffer ret = new StringBuffer();
176 for(int i=0; i<e.length; i++) {
177 if (i>0) ret.append(" ");
180 return ret.toString();
183 public Braces(Element[] e, Element sep) {
184 super("{"+join(e)+"}");
185 Element[] e2 = new Element[sep == null ? e.length+2 : e.length + 4];
187 e2[e2.length-1] = right;
190 e2[e2.length-2] = sep;
192 for(int i=0; i<e.length; i++) e2[i+(sep==null ? 1 : 2)] = e[i];
193 addAlternative(new Sequence.Singleton(e2));
194 addAlternative(new Sequence.Singleton(sep==null ? new Element[] { left, this, right} : new Element[] { left, sep, this, sep, right }));