@Override
    public Object visitWithin_time_range(SiddhiQLParser.Within_time_rangeContext ctx) {

        Within within;
        if (ctx.end_pattern == null) {
            within = Within.within((Expression) visit(ctx.start_pattern));
        } else {
            within = Within.within((Expression) visit(ctx.start_pattern), (Expression) visit(ctx.end_pattern));
        }
        populateQueryContext(within, ctx);
        return within;
    }
{@inheritDoc}
<p>The default implementation returns the result of calling
{@link #visitChildren} on {@code ctx}.</p>

@param ctx
modules/siddhi-query-compiler/src/main/java/io/siddhi/query/compiler/internal/SiddhiQLBaseVisitorImpl.java