Functions taking only Proof/View Arguments

Hello,

For general functions taking a view part and a non-view part, it looks like

fun foobar (pf: someview | a: sometype): sometype

What if it has only the view part? I tried this thing and it works, but the
syntax looks a little weird. Is it the right way of doing so? Just leave it
blank?

fun foobar (pf: someview | ): sometype

implement main () = …

val t = foobar (pf | )

Just wanna make sure.
Thank you!

The syntax is correct.

I often do something like:

val … = foo (pf | (none))

Oh, OK. Thanks for your answer!