Last updated 
Quantification operators
forall
  pact
(forall (x:string) y)  pact
(forall (x:string) y)- binds 
x: a - takes 
y: r - produces r
 - where a is any type
 - where r is any type
 
Bind a universally-quantified variable
Supported in properties only.
exists
  pact
(exists (x:string) y)  pact
(exists (x:string) y)- binds 
x: a - takes 
y: r - produces r
 - where a is any type
 - where r is any type
 
Bind an existentially-quantified variable
Supported in properties only.
column-of
  pact
(column-of t)  pact
(column-of t)- takes 
t:table - produces 
type 
The type of columns for a given table. Commonly used in conjunction with
quantification; e.g.:
(exists (col:(column-of accounts)) (column-written accounts col)).
Supported in properties only.