private NodeList<Stmt> buildLookaheadWithAmountCondition(
List<GLocation> location,
int lookahead,
int amount,
NodeList<FormalParameter> params,
NodeList<Expr> args) {
NodeList<Stmt> stmts = emptyList();
if (amount == 0) {
stmts = stmts.append(returnStmt().withExpr(LOOKAHEAD));
} else {
GContinuations c = new GContinuations(location, productions, lookahead > 0);
c.next();
Map<String, List<GLocation>> terminals = c.perTerminalLocations();
if (terminals.isEmpty()) {
stmts = stmts.append(returnStmt().withExpr(LOOKAHEAD));
} else {
for (Map.Entry<String, List<GLocation>> entry : terminals.entrySet()) {
String terminal = entry.getKey();
List<GLocation> following = entry.getValue();
stmts =
stmts.append(
ifStmt(
binaryExpr(
matchCall(terminal, literalExpr(lookahead)),
BinaryOp.NotEqual,
FAILED_LOOKAHEAD),
blockStmt()
.withStmts(
buildLookaheadWithAmountCondition(
following, lookahead + 1, amount - 1, params, args))));
}
}
}
return stmts;
}
private List<String> firstTerminalsOf(GExpansion expansion) {
GContinuations c = new GContinuations(expansion.location(), productions, false);
c.next();
return c.terminals();
}