@Override
    public Object[] visitStringNullableLiteralVarargs(final GremlinParser.StringNullableLiteralVarargsContext ctx) {
        if (ctx == null) {
            return new Object[0];
        }
        return ctx.children
                .stream()
                .filter(Objects::nonNull)
                .filter(p -> p instanceof GremlinParser.StringNullableLiteralContext)
                .map(p -> (GremlinParser.StringNullableLiteralContext) p)
                .map(antlr.genericVisitor::visitStringNullableLiteral)
                .toArray(Object[]::new);
    }
{@inheritDoc}
Generic literal collection returns a list of {@code Object}
gremlin-core/src/main/java/org/apache/tinkerpop/gremlin/language/grammar/GenericLiteralVisitor.java