public PathSegment visitCall(RexCall call) {
if ("ITEM".equals(call.getOperator().getName())) {
PathSegment mapOrArray = call.operands.get(0).accept(this);
if (mapOrArray != null) {
if (call.operands.get(1) instanceof RexLiteral) {
return mapOrArray.cloneWithNewChild(convertLiteral((RexLiteral) call.operands.get(1)));
}
return mapOrArray;
}
} else {
for (RexNode operand : call.operands) {