How does the Postgres daterange() function work?

This SQL:

select daterange(current_date, current_date);

Results in:

 daterange 
-----------
 empty
(1 row)

But the daterange() function does not seem to be documented. I've looked here and there. All I can see is that daterange() creates a daterange value with an exclusive end-date (hence the empty result).

Where can I find more about this function?

Is there a related function that can create a daterange value with an inclusive end-date?

PostgreSQL "daterange" is one of (built-in) rangetypes: int4range, int8range, numrange, tsrange, tstzrange, daterange.

And daterange is discrete range - is one whose element type has a well-defined “step”, such as integer or date.

Ranges have Inclusive and Exclusive Bounds. Default is '[)' - include lower and exclude upper bound. So

daterange(current_date, current_date)

is - from current_date to current_date excluded. This interval is "empty".

We can create daterange with bounds '[]'

daterange(current_date, current_date,'[]')

from "current_date" to "current_date+1", excluding "current_date+1".

This is equal to

daterange(current_date, current_date+1);

or

daterange(current_date, current_date+1,'[)');