/**
* Generate common code for a block of alternatives; return a postscript that needs to be
* generated at the end of the block. Other routines may append else-clauses and such for error
* checking before the postfix is generated.
*/
public void genCommonBlock(AlternativeBlock blk) {
for (int i = 0; i < blk.alternatives.size(); i++) {
Alternative alt = blk.getAlternativeAt(i);
AlternativeElement elem = alt.head;
// dump alt operator |
if (i > 0 && blk.alternatives.size() > 1) {
_println("");
print("|\t");
}
// Dump the alternative, starting with predicates
//
boolean save = firstElementInAlt;
firstElementInAlt = true;
tabs++; // in case we do a newline in alt, increase the tab indent
// RK: don't dump semantic/syntactic predicates
// only obscures grammar.
//
// Dump semantic predicates
//
// if (alt.semPred != null) {
// println("{" + alt.semPred + "}?");
// }
// Dump syntactic predicate
// if (alt.synPred != null) {
// genSynPred(alt.synPred);
// }
genAlt(alt);
tabs--;
firstElementInAlt = save;
}
}
/**
* Generate a textual representation of the lookahead set for a block.
*
* @param blk The block of interest
*/
public void genLookaheadSetForBlock(AlternativeBlock blk) {
// Find the maximal lookahead depth over all alternatives
int depth = 0;
for (int i = 0; i < blk.alternatives.size(); i++) {
Alternative alt = blk.getAlternativeAt(i);
if (alt.lookaheadDepth == GrammarAnalyzer.NONDETERMINISTIC) {
depth = grammar.maxk;
break;
} else if (depth < alt.lookaheadDepth) {
depth = alt.lookaheadDepth;
}
}
for (int i = 1; i <= depth; i++) {
Lookahead lookahead = grammar.theLLkAnalyzer.look(i, blk);
printSet(depth, i, lookahead);
}
}