Query block should become set block

[Broes De Cat]

Should become formula block (what to do with the variables?). Also, now needs double! { and }, which does not seem natural. Also an empty : if there are no vars is ugly.

[Bart Bogaerts]

You could also argue that this should become a "set" block. Since in fact that's what it is. In our case: a quantset,

It does not specifically represent a formula, but all tuples in a certain set.

For example

{x: true} cannot be represented as a formula without explicitly enumerating the "free" variables