What is Df(S)?

Where can I find information about it?

Hi! So, $df(S)$ will return time in Unix Time format (so seconds since epoch), you can find more options of df in the DF reference page. This is very useful in Kustom because it's what Kustom uses under the hood when doing math between dates.

So if you do

$ci(end, 0) - ci(start, 0)$ 

It will be the same as doing

$df(S, ci(start, 0)) - df(S, ci(end, 0))$

And it will return the seconds between the end and the start of the event, you can then use this if you like to format time, so, for example:

Next event will last $tf(ci(end, 0) - ci(start, 0))$ 

Will return "Next event will last 3 hours" with automatic formatting of time, or you can use

Next event will last $tf(ci(end, 0) - ci(start, 0), "H' hours and 'm' mins'")$ 

To return your custom time formatting, so "Next event will last 3 hours and 10 mins".