jasder
/
antlr
1
0
Fork 1
Code Issues Pull Requests Releases 1 Wiki Activity

reorg'd lexer ATN sim to fix bug 

[git-p4: depot-paths = "//depot/code/antlr4/main/": change = 9221]
This commit is contained in:
parrt 2011-10-27 19:33:45 -08:00
parent f44d03343a
commit 6576abf65f
2 changed files with 11 additions and 29 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

34
runtime/Java/src/org/antlr/v4/runtime/atn/LexerATNSimulator.java
View File

@ -36,7 +36,7 @@ import org.antlr.v4.runtime.misc.OrderedHashSet;
/** "dup" of ParserInterpreter */
public class LexerATNSimulator extends ATNSimulator {
public static boolean debug = true;
public static boolean dfa_debug = false;
public static boolean dfa_debug = true;
public static final int NUM_EDGES = 255;
protected Lexer recog;
@ -178,6 +178,9 @@ public class LexerATNSimulator extends ATNSimulator {
closure.addAll(s0);
if ( debug ) System.out.println("start state closure="+closure);
prevAccept = null;
prevAcceptIndex = -1;
OrderedHashSet<ATNConfig> reach = new OrderedHashSet<ATNConfig>();
int t = input.LA(1);
@ -189,27 +192,6 @@ public class LexerATNSimulator extends ATNSimulator {
ATNConfig c = closure.get(ci);
if ( debug ) System.out.println("testing "+getTokenName(t)+" at "+c.toString(recog, true));
// if ( c.state instanceof RuleStopState ) {
// if ( debug ) {
// System.out.println("in reach we hit accept state "+c+" index "+
// input.index()+", reach="+reach+
// ", prevAccept="+prevAccept+", prevIndex="+prevAcceptIndex);
// }
// if ( input.index() > prevAcceptIndex ) {
// // will favor prev accept at same index so "int" is keyword not ID
// prevAccept = c;
// prevAcceptIndex = input.index();
// }
//
// // if we reach lexer accept state, toss out any configs in rest
// // of configs work list associated with this rule (config.alt);
// // that rule is done. this is how we cut off nongreedy .+ loops.
// deleteWildcardConfigsForAlt(closure, ci, c.alt);
//
// // move to next char, looking for longer match
// // (we continue processing if there are states in reach)
// }
int n = c.state.getNumberOfTransitions();
for (int ti=0; ti<n; ti++) { // for each transition
Transition trans = c.state.transition(ti);
@ -221,11 +203,13 @@ public class LexerATNSimulator extends ATNSimulator {
}
if ( reach.size()==0 ) {
// we reached closure state for sure, make sure it's defined.
// worst case, we define s0 from start state configs.
// we reached state associated with closure for sure, so
// make sure it's defined. worst case, we define s0 from
// start state configs.
DFAState from = addDFAState(closure);
// we got nowhere on t, don't throw out this knowledge; it'd
// cause a failover from DFA later.
// cause a failover from DFA later. Don't track EOF edges
// from stop states, though.
if ( t!=Token.EOF ) addDFAEdge(from, t, ERROR);
break;
}

6
tool/playground/L.g
View File

@ -1,5 +1,3 @@
lexer grammar L;
HexLiteral : '0' 'x' HexDigit+ ;
DecimalLiteral : ('0' | '1'..'9' '0'..'9'*) ;
fragment HexDigit : ('0'..'9'|'a'..'f');
WS : (' '|'\n')+ ;
HexLiteral : '0' 'x' '9' ;
DecimalLiteral : '0' ;