Is it possible to return Daily Highest if I only use intraday data in a session?

e.g. Data is 5 min. but I want to use Highest(High,30,0) which returns the highest High of the last 30 days.

Maybe I could workaround with a function which builds an array of the highs of the day and then return Max?

But I would prefer a built in function.

Minor work around

TodayHighBar and TodayLowBar give you the bars ago that todays high and low occured.

So , High[TodayHighBar] will give you todays high.