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# jay skeleton
# character in column 1 determines outcome...
# # is a comment
# . is copied
# t is copied as //t if -t is set
# other lines are interpreted to call jay procedures
.// created by jay 0.7 (c) 1998 Axel.Schreiner@informatik.uni-osnabrueck.de
.
prolog ## %{ ... %} prior to the first %%
.
. /** simplified error message.
. @see <a href="#yyerror(java.lang.String, java.lang.String[])">yyerror</a>
. */
. public void yyerror (string message) {
. yyerror(message, null);
. }
.
. /** (syntax) error message.
. Can be overwritten to control message format.
. @param message text to be displayed.
. @param expected vector of acceptable tokens, if available.
. */
. public void yyerror (string message, string[] expected) {
. if ((expected != null) && (expected.Length > 0)) {
. StringBuilder sb = new StringBuilder();
. sb.AppendFormat("{0}, expecting", message);
. for (int n = 0; n < expected.Length; ++ n)
. sb.AppendFormat(" {0}", expected[n]);
. thread.CompileError(sb.ToString());
. } else
. thread.CompileError (message);
. }
.
. /** debugging support, requires the package jay.yydebug.
. Set to null to suppress debugging messages.
. */
t protected yydebug.yyDebug yydebug;
.
debug ## tables for debugging support
.
. /** index-checked interface to yyNames [].
. @param token single character or %token value.
. @return token name or [illegal] or [unknown].
. */
t public static string yyname (int token) {
t if ((token < 0) || (token > yyNames .Length)) return "[illegal]";
t string name;
t if ((name = yyNames [token]) != null) return name;
t return "[unknown]";
t }
.
. /** computes list of expected tokens on error by tracing the tables.
. @param state for which to compute the list.
. @return list of token names.
. */
. protected string[] yyExpecting (int state) {
. int token, n, len = 0;
. bool[] ok = new bool[yyNames .Length];
.
. if ((n = yySindex[state]) != 0)
. for (token = n < 0 ? -n : 0;
. (token < yyNames .Length) && (n+token < yyTable.Length); ++ token)
. if (yyCheck[n+token] == token && !ok[token] && yyNames [token] != null) {
. ++ len;
. ok[token] = true;
. }
. if ((n = yyRindex[state]) != 0)
. for (token = n < 0 ? -n : 0;
. (token < yyNames .Length) && (n+token < yyTable.Length); ++ token)
. if (yyCheck[n+token] == token && !ok[token] && yyNames [token] != null) {
. ++ len;
. ok[token] = true;
. }
.
. string [] result = new string[len];
. for (n = token = 0; n < len; ++ token)
. if (ok[token]) result[n++] = yyNames [token];
. return result;
. }
.
. /** the generated parser, with debugging messages.
. Maintains a state and a value stack, currently with fixed maximum size.
. @param yyLex scanner.
. @param yydebug debug message writer implementing yyDebug, or null.
. @return result of the last reduction, if any.
. @throws yyException on irrecoverable parse error.
. */
. public Object yyparse (yyParser.yyInput yyLex, Object yydebug)
. {
t this.yydebug = (yydebug.yyDebug)yydebug;
. return yyparse(yyLex);
. }
.
. /** initial size and increment of the state/value stack [default 256].
. This is not final so that it can be overwritten outside of invocations
. of yyparse().
. */
. protected int yyMax;
.
. /** executed at the beginning of a reduce action.
. Used as $$ = yyDefault($1), prior to the user-specified action, if any.
. Can be overwritten to provide deep copy, etc.
. @param first value for $1, or null.
. @return first.
. */
. protected Object yyDefault (Object first) {
. return first;
. }
.
. /** the generated parser.
. Maintains a state and a value stack, currently with fixed maximum size.
. @param yyLex scanner.
. @return result of the last reduction, if any.
. @throws yyException on irrecoverable parse error.
. */
. public Object yyparse (yyParser.yyInput yyLex)
. {
. if (yyMax <= 0) yyMax = 256; // initial size
. int yyState = 0; // state stack ptr
. int [] yyStates = new int[yyMax]; // state stack
. Object yyVal = null; // value stack ptr
. Object [] yyVals = new Object[yyMax]; // value stack
. int yyToken = -1; // current input
. int yyErrorFlag = 0; // #tks to shift
.
local ## %{ ... %} after the first %%
. int yyTop = 0;
. goto skip;
. yyLoop:
. yyTop++;
. skip:
. for (;; ++ yyTop) {
. if (yyTop >= yyStates.Length) { // dynamically increase
. int[] i = new int[yyStates.Length+yyMax];
. System.Array.Copy(yyStates, i, 0);
. yyStates = i;
. Object[] o = new Object[yyVals.Length+yyMax];
. System.Array.Copy(yyVals, o, 0);
. yyVals = o;
. }
. yyStates[yyTop] = yyState;
. yyVals[yyTop] = yyVal;
t if (yydebug != null) yydebug.push(yyState, yyVal);
.
. yyDiscarded: for (;;) { // discarding a token does not change stack
. int yyN;
. if ((yyN = yyDefRed[yyState]) == 0) { // else [default] reduce (yyN)
. if (yyToken < 0) {
. yyToken = yyLex.advance() ? yyLex.token() : 0;
t if (yydebug != null)
t yydebug.lex(yyState, yyToken, yyname(yyToken), yyLex.value());
. }
. if ((yyN = yySindex[yyState]) != 0 && ((yyN += yyToken) >= 0)
. && (yyN < yyTable.Length) && (yyCheck[yyN] == yyToken)) {
t if (yydebug != null)
t yydebug.shift(yyState, yyTable[yyN], yyErrorFlag-1);
. yyState = yyTable[yyN]; // shift to yyN
. yyVal = yyLex.value();
. yyToken = -1;
. if (yyErrorFlag > 0) -- yyErrorFlag;
. goto yyLoop;
. }
. if ((yyN = yyRindex[yyState]) != 0 && (yyN += yyToken) >= 0
. && yyN < yyTable.Length && yyCheck[yyN] == yyToken)
. yyN = yyTable[yyN]; // reduce (yyN)
. else
. switch (yyErrorFlag) {
.
. case 0:
. yyerror("syntax error", yyExpecting(yyState));
t if (yydebug != null) yydebug.error("syntax error");
. goto case 1;
. case 1: case 2:
. yyErrorFlag = 3;
. do {
. if ((yyN = yySindex[yyStates[yyTop]]) != 0
. && (yyN += Token.yyErrorCode) >= 0 && yyN < yyTable.Length
. && yyCheck[yyN] == Token.yyErrorCode) {
t if (yydebug != null)
t yydebug.shift(yyStates[yyTop], yyTable[yyN], 3);
. yyState = yyTable[yyN];
. yyVal = yyLex.value();
. goto yyLoop;
. }
t if (yydebug != null) yydebug.pop(yyStates[yyTop]);
. } while (-- yyTop >= 0);
t if (yydebug != null) yydebug.reject();
. throw new yyParser.yyException("irrecoverable syntax error");
.
. case 3:
. if (yyToken == 0) {
t if (yydebug != null) yydebug.reject();
. throw new yyParser.yyException("irrecoverable syntax error at end-of-file");
. }
t if (yydebug != null)
t yydebug.discard(yyState, yyToken, yyname(yyToken),
t yyLex.value());
. yyToken = -1;
. goto yyDiscarded; // leave stack alone
. }
. }
. int yyV = yyTop + 1-yyLen[yyN];
t if (yydebug != null)
t yydebug.reduce(yyState, yyStates[yyV-1], yyN, yyRule[yyN], yyLen[yyN]);
. yyVal = yyDefault(yyV > yyTop ? null : yyVals[yyV]);
. switch (yyN) {
actions ## code from the actions within the grammar
. }
. yyTop -= yyLen[yyN];
. yyState = yyStates[yyTop];
. int yyM = yyLhs[yyN];
. if (yyState == 0 && yyM == 0) {
t if (yydebug != null) yydebug.shift(0, yyFinal);
. yyState = yyFinal;
. if (yyToken < 0) {
. yyToken = yyLex.advance() ? yyLex.token() : 0;
t if (yydebug != null)
t yydebug.lex(yyState, yyToken,yyname(yyToken), yyLex.value());
. }
. if (yyToken == 0) {
t if (yydebug != null) yydebug.accept(yyVal);
. return yyVal;
. }
. goto yyLoop;
. }
. if (((yyN = yyGindex[yyM]) != 0) && ((yyN += yyState) >= 0)
. && (yyN < yyTable.Length) && (yyCheck[yyN] == yyState))
. yyState = yyTable[yyN];
. else
. yyState = yyDgoto[yyM];
t if (yydebug != null) yydebug.shift(yyStates[yyTop], yyState);
. goto yyLoop;
. }
. }
. }
.
tables ## tables for rules, default reduction, and action calls
.
epilog ## text following second %%
.namespace yydebug {
. using System;
. public interface yyDebug {
. void push (int state, Object value);
. void lex (int state, int token, string name, Object value);
. void shift (int from, int to, int errorFlag);
. void pop (int state);
. void discard (int state, int token, string name, Object value);
. void reduce (int from, int to, int rule, string text, int len);
. void shift (int from, int to);
. void accept (Object value);
. void error (string message);
. void reject ();
. }
.
. class yyDebugSimple : yyDebug {
. void println (string s){
. Console.WriteLine (s);
. }
.
. public void push (int state, Object value) {
. println ("push\tstate "+state+"\tvalue "+value);
. }
.
. public void lex (int state, int token, string name, Object value) {
. println("lex\tstate "+state+"\treading "+name+"\tvalue "+value);
. }
.
. public void shift (int from, int to, int errorFlag) {
. switch (errorFlag) {
. default: // normally
. println("shift\tfrom state "+from+" to "+to);
. break;
. case 0: case 1: case 2: // in error recovery
. println("shift\tfrom state "+from+" to "+to
. +"\t"+errorFlag+" left to recover");
. break;
. case 3: // normally
. println("shift\tfrom state "+from+" to "+to+"\ton error");
. break;
. }
. }
.
. public void pop (int state) {
. println("pop\tstate "+state+"\ton error");
. }
.
. public void discard (int state, int token, string name, Object value) {
. println("discard\tstate "+state+"\ttoken "+name+"\tvalue "+value);
. }
.
. public void reduce (int from, int to, int rule, string text, int len) {
. println("reduce\tstate "+from+"\tuncover "+to
. +"\trule ("+rule+") "+text);
. }
.
. public void shift (int from, int to) {
. println("goto\tfrom state "+from+" to "+to);
. }
.
. public void accept (Object value) {
. println("accept\tvalue "+value);
. }
.
. public void error (string message) {
. println("error\t"+message);
. }
.
. public void reject () {
. println("reject");
. }
.
. }
.}
.// %token constants
. class Token {
tokens public const int
. }
. namespace yyParser {
. using System;
. /** thrown for irrecoverable syntax errors and stack overflow.
. */
. public class yyException : System.Exception {
. public yyException (string message) : base (message) {
. }
. }
.
. /** must be implemented by a scanner object to supply input to the parser.
. */
. public interface yyInput {
. /** move on to next token.
. @return false if positioned beyond tokens.
. @throws IOException on input error.
. */
. bool advance (); // throws java.io.IOException;
. /** classifies current token.
. Should not be called if advance() returned false.
. @return current %token or single character.
. */
. int token ();
. /** associated with current token.
. Should not be called if advance() returned false.
. @return value for token().
. */
. Object value ();
. }
. }
.} // close outermost namespace, that MUST HAVE BEEN opened in the prolog