Data.SBV.Examples.Uninterpreted.Sort

Demonstrates uninterpreted sorts, together with axioms.

Documentation

data Q

A new data-type that we expect to use in an uninterpreted fashion in the backend SMT solver. Note the custom deriving clause, which takes care of most of the boilerplate.

Constructors

Q

Instances

Eq Q

Data Q

Ord Q

Typeable Q

SymWord Q

We need SymWord and HasKind instances, but default definitions are always sufficient for uninterpreted sorts, so all we do is to declare them as such. Note that, starting with GHC 7.6.1, we will be able to simply derive these classes as well. (See http://hackage.haskell.org/trac/ghc/ticket/5462.)

HasKind Q

f :: SBV Q -> SBV Q

Declare an uninterpreted function that works over Q's

t1 :: IO SatResult

A satisfiable example, stating that there is an element of the domain Q such that f returns a different element. Note that this is valid only when the domain Q has at least two elements. We have:

>>> t1
Satisfiable. Model:
  x = Q!val!0 :: Q

t2 :: IO SatResult

This is a variant on the first example, except we also add an axiom for the sort, stating that the domain Q has only one element. In this case the problem naturally becomes unsat. We have:

>>> t2
Unsatisfiable