Data.SBV.Control

Control sublanguage for interacting with SMT solvers.

Documentation

In certain cases, the user might want to take over the communication with the solver, programmatically querying the engine and issuing commands accordingly. Queries can be extremely powerful as they allow direct control of the solver. Here's a simple example:

    module Test where

    import Data.SBV
    import Data.SBV.Control  -- queries require this module to be imported!

    test :: Symbolic (Maybe (Integer, Integer))
    test = do x <- sInteger "x"   -- a free variable named "x"
              y <- sInteger "y"   -- a free variable named "y"

              -- require the sum to be 10
              constrain $ x + y .== 10

              -- Go into the Query mode
              query $ do
                    -- Query the solver: Are the constraints satisfiable?
                    cs <- checkSat
                    case cs of
                      Unk    -> error "Solver said unknown!"
                      DSat{} -> error "Solver said DSat!"
                      Unsat  -> return Nothing -- no solution!
                      Sat    -> -- Query the values:
                                do xv <- getValue x
                                   yv <- getValue y

                                   io $ putStrLn $ "Solver returned: " ++ show (xv, yv)

                                   -- We can now add new constraints,
                                   -- Or perform arbitrary computations and tell
                                   -- the solver anything we want!
                                   constrain $ x .> literal xv + literal yv

                                   -- call checkSat again
                                   csNew <- checkSat
                                   case csNew of
                                     Unk    -> error "Solver said unknown!"
                                     DSat{} -> error "Solver said DSat!"
                                     Unsat  -> return Nothing
                                     Sat    -> do xv2 <- getValue x
                                                  yv2 <- getValue y

                                                  return $ Just (xv2, yv2)

Note the type of test: it returns an optional pair of integers in the Symbolic monad. We turn it into an IO value with the runSMT function: (There's also runSMTWith that uses a user specified solver instead of the default. Note that z3 is best supported (and tested), if you use another solver your results may vary!)

    pair :: IO (Maybe (Integer, Integer))
    pair = runSMT test

When run, this can return:

*Test> pair
Solver returned: (10,0)
Just (11,-1)

demonstrating that the user has full contact with the solver and can guide it as the program executes. SBV provides access to many SMTLib features in the query mode, as exported from this very module.

For other examples see:

• Documentation.SBV.Examples.Queries.AllSat: Simulating SBV's allSat using queries.
• Documentation.SBV.Examples.Queries.CaseSplit: Performing a case-split during a query.
• Documentation.SBV.Examples.Queries.Enums: Using enumerations in queries.
• Documentation.SBV.Examples.Queries.FourFours: Solution to a fun arithmetic puzzle, coded using queries.
• Documentation.SBV.Examples.Queries.GuessNumber: The famous number guessing game.
• Documentation.SBV.Examples.Queries.UnsatCore: Extracting unsat-cores using queries.
• Documentation.SBV.Examples.Queries.Interpolants: Extracting interpolants using queries.

User queries

class MonadIO m => ExtractIO m where

Monads which support IO operations and can extract all IO behavior for interoperation with functions like catches, which takes an IO action in negative position. This function can not be implemented for transformers like ReaderT r or StateT s, whose resultant IO actions are a function of some environment or state.

Methods

extractIO :: m a -> IO (m a)

Law: the m a yielded by IO is pure with respect to IO.

Instances

ExtractIO IO

Trivial IO extraction for IO.

Defined in Data.SBV.Utils.ExtractIO

Methods

extractIO :: IO a -> IO (IO a)

ExtractIO m => ExtractIO (MaybeT m)

IO extraction for MaybeT.

Defined in Data.SBV.Utils.ExtractIO

Methods

extractIO :: MaybeT m a -> IO (MaybeT m a)

ExtractIO m => ExtractIO (ExceptT e m)

IO extraction for ExceptT.

Defined in Data.SBV.Utils.ExtractIO

Methods

extractIO :: ExceptT e m a -> IO (ExceptT e m a)

(Monoid w, ExtractIO m) => ExtractIO (WriterT w m)

IO extraction for lazy WriterT.

Defined in Data.SBV.Utils.ExtractIO

Methods

extractIO :: WriterT w m a -> IO (WriterT w m a)

(Monoid w, ExtractIO m) => ExtractIO (WriterT w m)

IO extraction for strict WriterT.

Defined in Data.SBV.Utils.ExtractIO

Methods

extractIO :: WriterT w m a -> IO (WriterT w m a)

class Monad m => MonadQuery m where

Computations which support query operations.

Minimal complete definition

Nothing

Methods

queryState :: m State

default queryState :: (MonadTrans t, MonadQuery m', m ~ t m') => m State

Instances

MonadQuery Q

Defined in Documentation.SBV.Examples.Transformers.SymbolicEval

Methods

queryState :: Q State

Monad m => MonadQuery (QueryT m)

Defined in Data.SBV.Core.Symbolic

Methods

queryState :: QueryT m State

MonadQuery m => MonadQuery (MaybeT m)

Defined in Data.SBV.Core.Symbolic

Methods

queryState :: MaybeT m State

MonadQuery m => MonadQuery (ExceptT e m)

Defined in Data.SBV.Core.Symbolic

Methods

queryState :: ExceptT e m State

MonadQuery m => MonadQuery (ReaderT r m)

Defined in Data.SBV.Core.Symbolic

Methods

queryState :: ReaderT r m State

MonadQuery m => MonadQuery (StateT s m)

Defined in Data.SBV.Core.Symbolic

Methods

queryState :: StateT s m State

MonadQuery m => MonadQuery (StateT s m)

Defined in Data.SBV.Core.Symbolic

Methods

queryState :: StateT s m State

(MonadQuery m, Monoid w) => MonadQuery (WriterT w m)

Defined in Data.SBV.Core.Symbolic

Methods

queryState :: WriterT w m State

(MonadQuery m, Monoid w) => MonadQuery (WriterT w m)

Defined in Data.SBV.Core.Symbolic

Methods

queryState :: WriterT w m State

class Queriable m a b | a -> b where

An queriable value. This is a generalization of the Fresh class, in case one needs to be more specific about how projections/embeddings are done.

Methods

create :: QueryT m a

^ Create a new symbolic value of type a

project :: a -> QueryT m b

^ Extract the current value in a SAT context

embed :: b -> QueryT m a

^ Create a literal value. Morally, embed and project are inverses of each other via the QueryT monad transformer.

Instances

(MonadIO m, SymVal a) => Queriable m (SBV a) a

Generic Queriable instance for SymVal values

Defined in Data.SBV.Control.Utils

Methods

create :: QueryT m (SBV a)

project :: SBV a -> QueryT m a

embed :: a -> QueryT m (SBV a)

Queriable IO (AppS Integer) (AppC Integer)

Queriable instance for the program state

Defined in Documentation.SBV.Examples.WeakestPreconditions.Append

Methods

create :: QueryT IO (AppS Integer)

project :: AppS Integer -> QueryT IO (AppC Integer)

embed :: AppC Integer -> QueryT IO (AppS Integer)

Queriable IO (LenS Integer) (LenC Integer)

We have to write the bijection between LenS and LenC explicitly. Luckily, the definition is more or less boilerplate.

Defined in Documentation.SBV.Examples.WeakestPreconditions.Length

Methods

create :: QueryT IO (LenS Integer)

project :: LenS Integer -> QueryT IO (LenC Integer)

embed :: LenC Integer -> QueryT IO (LenS Integer)

(MonadIO m, SymVal a, Foldable t, Traversable t, Fresh m (t (SBV a))) => Queriable m (t (SBV a)) (t a)

Generic Queriable instance for things that are Fresh and look like containers:

Defined in Data.SBV.Control.Utils

Methods

create :: QueryT m (t (SBV a))

project :: t (SBV a) -> QueryT m (t a)

embed :: t a -> QueryT m (t (SBV a))

class Fresh m a where

Create a fresh variable of some type in the underlying query monad transformer. For further control on how these variables are projected and embedded, see the Queriable class.

Methods

fresh :: QueryT m a

Instances

Fresh IO (S SInteger)

Fresh instance for our state

Defined in Documentation.SBV.Examples.ProofTools.BMC

Methods

fresh :: QueryT IO (S SInteger)

Fresh IO (S SInteger)

Fresh instance for our state

Defined in Documentation.SBV.Examples.ProofTools.Fibonacci

Methods

fresh :: QueryT IO (S SInteger)

Fresh IO (S SInteger)

Fresh instance for our state

Defined in Documentation.SBV.Examples.ProofTools.Strengthen

Methods

fresh :: QueryT IO (S SInteger)

Fresh IO (S SInteger)

Fresh instance for our state

Defined in Documentation.SBV.Examples.ProofTools.Sum

Methods

fresh :: QueryT IO (S SInteger)

SymVal a => Fresh IO (IncS (SBV a))

Fresh instance for the program state

Defined in Documentation.SBV.Examples.WeakestPreconditions.Basics

Methods

fresh :: QueryT IO (IncS (SBV a))

SymVal a => Fresh IO (FibS (SBV a))

Fresh instance for the program state

Defined in Documentation.SBV.Examples.WeakestPreconditions.Fib

Methods

fresh :: QueryT IO (FibS (SBV a))

SymVal a => Fresh IO (GCDS (SBV a))

Fresh instance for the program state

Defined in Documentation.SBV.Examples.WeakestPreconditions.GCD

Methods

fresh :: QueryT IO (GCDS (SBV a))

SymVal a => Fresh IO (DivS (SBV a))

Fresh instance for the program state

Defined in Documentation.SBV.Examples.WeakestPreconditions.IntDiv

Methods

fresh :: QueryT IO (DivS (SBV a))

SymVal a => Fresh IO (SqrtS (SBV a))

Fresh instance for the program state

Defined in Documentation.SBV.Examples.WeakestPreconditions.IntSqrt

Methods

fresh :: QueryT IO (SqrtS (SBV a))

SymVal a => Fresh IO (SumS (SBV a))

Fresh instance for the program state

Defined in Documentation.SBV.Examples.WeakestPreconditions.Sum

Methods

fresh :: QueryT IO (SumS (SBV a))

type Query = QueryT IO

A query is a user-guided mechanism to directly communicate and extract results from the solver.

query :: Query a -> Symbolic a

Run a custom query

Create a fresh variable

freshVar_ :: SymVal a => Query (SBV a)

Similar to freshVar, except creates unnamed variable.

NB. For a version which generalizes over the underlying monad, see freshVar_

freshVar :: SymVal a => String -> Query (SBV a)

Create a fresh variable in query mode. You should prefer creating input variables using sBool, sInt32, etc., which act as primary inputs to the model and can be existential or universal. Use freshVar only in query mode for anonymous temporary variables. Such variables are always existential. Note that freshVar should hardly be needed: Your input variables and symbolic expressions should suffice for most major use cases.

NB. For a version which generalizes over the underlying monad, see freshVar

Create a fresh array

freshArray_ :: (SymArray array, HasKind a, HasKind b) => Maybe (SBV b) -> Query (array a b)

Similar to freshArray, except creates unnamed array.

NB. For a version which generalizes over the underlying monad, see freshArray_

freshArray :: (SymArray array, HasKind a, HasKind b) => String -> Maybe (SBV b) -> Query (array a b)

Create a fresh array in query mode. Again, you should prefer creating arrays before the queries start using newArray, but this method can come in handy in occasional cases where you need a new array after you start the query based interaction.

NB. For a version which generalizes over the underlying monad, see freshArray

Checking satisfiability

data CheckSatResult

Result of a checkSat or checkSatAssuming call.

Constructors

Sat

Satisfiable: A model is available, which can be queried with getValue.

DSat (Maybe String)

Delta-satisfiable: A delta-sat model is available. String is the precision info, if available.

Unsat

Unsatisfiable: No model is available. Unsat cores might be obtained via getUnsatCore.

Unk

Unknown: Use getUnknownReason to obtain an explanation why this might be the case.

Instances

Show CheckSatResult

Defined in Data.SBV.Control.Types

Methods

showsPrec :: Int -> CheckSatResult -> ShowS

show :: CheckSatResult -> String

showList :: [CheckSatResult] -> ShowS

Eq CheckSatResult

Defined in Data.SBV.Control.Types

Methods

(==) :: CheckSatResult -> CheckSatResult -> Bool

(/=) :: CheckSatResult -> CheckSatResult -> Bool

checkSat :: Query CheckSatResult

Check for satisfiability.

NB. For a version which generalizes over the underlying monad, see checkSat

ensureSat :: Query ()

Ensure that the current context is satisfiable. If not, this function will throw an error.

NB. For a version which generalizes over the underlying monad, see ensureSat

checkSatUsing :: String -> Query CheckSatResult

Check for satisfiability with a custom check-sat-using command.

NB. For a version which generalizes over the underlying monad, see checkSatUsing

checkSatAssuming :: [SBool] -> Query CheckSatResult

Check for satisfiability, under the given conditions. Similar to checkSat except it allows making further assumptions as captured by the first argument of booleans. (Also see checkSatAssumingWithUnsatisfiableSet for a variant that returns the subset of the given assumptions that led to the Unsat conclusion.)

NB. For a version which generalizes over the underlying monad, see checkSatAssuming

checkSatAssumingWithUnsatisfiableSet :: [SBool] -> Query (CheckSatResult, Maybe [SBool])

Check for satisfiability, under the given conditions. Returns the unsatisfiable set of assumptions. Similar to checkSat except it allows making further assumptions as captured by the first argument of booleans. If the result is Unsat, the user will also receive a subset of the given assumptions that led to the Unsat conclusion. Note that while this set will be a subset of the inputs, it is not necessarily guaranteed to be minimal.

You must have arranged for the production of unsat assumptions first via

    setOption $ ProduceUnsatAssumptions True

for this call to not error out!

Usage note: getUnsatCore is usually easier to use than checkSatAssumingWithUnsatisfiableSet, as it allows the use of named assertions, as obtained by namedConstraint. If getUnsatCore fills your needs, you should definitely prefer it over checkSatAssumingWithUnsatisfiableSet.

NB. For a version which generalizes over the underlying monad, see checkSatAssumingWithUnsatisfiableSet

Querying the solver

Extracting values

getValue :: SymVal a => SBV a -> Query a

Get the value of a term.

NB. For a version which generalizes over the underlying monad, see getValue

registerUISMTFunction :: (MonadIO m, SolverContext m, MonadSymbolic m) => SMTFunction fun a r => fun -> m ()

Registering an uninterpreted SMT function. This is typically not necessary as uses of the UI function itself will register it automatically. But there are cases where doing this explicitly can come in handy.

getFunction :: (SymVal a, SymVal r, SMTFunction fun a r) => fun -> Query ([(a, r)], r)

Get the value of an uninterpreted function, as a list of domain, value pairs. The final value is the "else" clause, i.e., what the function maps values outside of the domain of the first list.

getUninterpretedValue :: HasKind a => SBV a -> Query String

Get the value of an uninterpreted sort, as a String

NB. For a version which generalizes over the underlying monad, see getUninterpretedValue

getModel :: Query SMTModel

Collect model values. It is implicitly assumed that we are in a check-sat context. See getSMTResult for a variant that issues a check-sat first and returns an SMTResult.

NB. For a version which generalizes over the underlying monad, see getModel

getAssignment :: Query [(String, Bool)]

Retrieve the assignment. This is a lightweight version of getValue, where the solver returns the truth value for all named subterms of type Bool.

You must have first arranged for assignments to be produced via

    setOption $ ProduceAssignments True

for this call to not error out!

NB. For a version which generalizes over the underlying monad, see getAssignment

getSMTResult :: Query SMTResult

Issue check-sat and get an SMT Result out.

NB. For a version which generalizes over the underlying monad, see getSMTResult

getUnknownReason :: Query SMTReasonUnknown

Get the reason unknown. Only internally used.

NB. For a version which generalizes over the underlying monad, see getUnknownReason

getObservables :: Query [(Name, CV)]

Get the observables recorded during a query run.

NB. For a version which generalizes over the underlying monad, see getObservables

Extracting the unsat core

getUnsatCore :: Query [String]

Retrieve the unsat-core. Note you must have arranged for unsat cores to be produced first via

    setOption $ ProduceUnsatCores True

for this call to not error out!

NB. There is no notion of a minimal unsat-core, in case unsatisfiability can be derived in multiple ways. Furthermore, Z3 does not guarantee that the generated unsat core does not have any redundant assertions either, as doing so can incur a performance penalty. (There might be assertions in the set that is not needed.) To ensure all the assertions in the core are relevant, use:

    setOption $ OptionKeyword ":smt.core.minimize" ["true"]

Note that this only works with Z3.

NB. For a version which generalizes over the underlying monad, see getUnsatCore

Extracting a proof

getProof :: Query String

Retrieve the proof. Note you must have arranged for proofs to be produced first via

    setOption $ ProduceProofs True

for this call to not error out!

A proof is simply a String, as returned by the solver. In the future, SBV might provide a better datatype, depending on the use cases. Please get in touch if you use this function and can suggest a better API.

NB. For a version which generalizes over the underlying monad, see getProof

Extracting interpolants

getInterpolantMathSAT :: [String] -> Query String

Interpolant extraction for MathSAT. Compare with getInterpolantZ3, which performs similar function (but with a different use model) in Z3.

Retrieve an interpolant after an Unsat result is obtained. Note you must have arranged for interpolants to be produced first via

    setOption $ ProduceInterpolants True

for this call to not error out!

To get an interpolant for a pair of formulas A and B, use a constrainWithAttribute call to attach interplation groups to A and B. Then call getInterpolantMathSAT ["A"], assuming those are the names you gave to the formulas in the A group.

An interpolant for A and B is a formula I such that:

       A .=> I
   and B .=> sNot I

That is, it's evidence that A and B cannot be true together since A implies I but B implies not I; establishing that A and B cannot be satisfied at the same time. Furthermore, I will have only the symbols that are common to A and B.

NB. Interpolant extraction isn't standardized well in SMTLib. Currently both MathSAT and Z3 support them, but with slightly differing APIs. So, we support two APIs with slightly differing types to accommodate both. See Documentation.SBV.Examples.Queries.Interpolants for example usages in these solvers.

NB. For a version which generalizes over the underlying monad, see getInterpolantMathSAT

getInterpolantZ3 :: [SBool] -> Query String

Interpolant extraction for z3. Compare with getInterpolantMathSAT, which performs similar function (but with a different use model) in MathSAT.

Unlike the MathSAT variant, you should simply call getInterpolantZ3 on symbolic booleans to retrieve the interpolant. Do not call checkSat or create named constraints. This makes it harder to identify formulas, but the current state of affairs in interpolant API requires this kludge.

An interpolant for A and B is a formula I such that:

       A ==> I
   and B ==> not I

That is, it's evidence that A and B cannot be true together since A implies I but B implies not I; establishing that A and B cannot be satisfied at the same time. Furthermore, I will have only the symbols that are common to A and B.

In Z3, interpolants generalize to sequences: If you pass more than two formulas, then you will get a sequence of interpolants. In general, for N formulas that are not satisfiable together, you will be returned N-1 interpolants. If formulas are A1 .. An, then interpolants will be I1 .. I(N-1), such that A1 ==> I1, A2 /\ I1 ==> I2, A3 /\ I2 ==> I3, ..., and finally AN ===> not I(N-1).

Currently, SBV only returns simple and sequence interpolants, and does not support tree-interpolants. If you need these, please get in touch. Furthermore, the result will be a list of mere strings representing the interpolating formulas, as opposed to a more structured type. Please get in touch if you use this function and can suggest a better API.

NB. Interpolant extraction isn't standardized well in SMTLib. Currently both MathSAT and Z3 support them, but with slightly differing APIs. So, we support two APIs with slightly differing types to accommodate both. See Documentation.SBV.Examples.Queries.Interpolants for example usages in these solvers.

NB. For a version which generalizes over the underlying monad, see getInterpolantZ3

Extracting assertions

getAssertions :: Query [String]

Retrieve assertions. Note you must have arranged for assertions to be available first via

    setOption $ ProduceAssertions True

for this call to not error out!

Note that the set of assertions returned is merely a list of strings, just like the case for getProof. In the future, SBV might provide a better datatype, depending on the use cases. Please get in touch if you use this function and can suggest a better API.

NB. For a version which generalizes over the underlying monad, see getAssertions

Getting solver information

data SMTInfoFlag

Collectable information from the solver.

Constructors

AllStatistics

AssertionStackLevels

Authors

ErrorBehavior

Name

ReasonUnknown

Version

InfoKeyword String

Instances

Show SMTInfoFlag

Defined in Data.SBV.Control.Types

Methods

showsPrec :: Int -> SMTInfoFlag -> ShowS

show :: SMTInfoFlag -> String

showList :: [SMTInfoFlag] -> ShowS

data SMTErrorBehavior

Behavior of the solver for errors.

Constructors

ErrorImmediateExit

ErrorContinuedExecution

Instances

Show SMTErrorBehavior

Defined in Data.SBV.Control.Types

Methods

showsPrec :: Int -> SMTErrorBehavior -> ShowS

show :: SMTErrorBehavior -> String

showList :: [SMTErrorBehavior] -> ShowS

data SMTInfoResponse

Collectable information from the solver.

Constructors

Resp_Unsupported

Resp_AllStatistics [(String, String)]

Resp_AssertionStackLevels Integer

Resp_Authors [String]

Resp_Error SMTErrorBehavior

Resp_Name String

Resp_ReasonUnknown SMTReasonUnknown

Resp_Version String

Resp_InfoKeyword String [String]

Instances

Show SMTInfoResponse

Defined in Data.SBV.Control.Types

Methods

showsPrec :: Int -> SMTInfoResponse -> ShowS

show :: SMTInfoResponse -> String

showList :: [SMTInfoResponse] -> ShowS

getInfo :: SMTInfoFlag -> Query SMTInfoResponse

Ask solver for info.

NB. For a version which generalizes over the underlying monad, see getInfo

getOption :: (a -> SMTOption) -> Query (Maybe SMTOption)

Retrieve the value of an 'SMTOption.' The curious function argument is on purpose here, simply pass the constructor name. Example: the call getOption ProduceUnsatCores will return either Nothing or Just (ProduceUnsatCores True) or Just (ProduceUnsatCores False).

Result will be Nothing if the solver does not support this option.

NB. For a version which generalizes over the underlying monad, see getOption

Entering and exiting assertion stack

getAssertionStackDepth :: Query Int

The current assertion stack depth, i.e., #push - #pops after start. Always non-negative.

NB. For a version which generalizes over the underlying monad, see getAssertionStackDepth

push :: Int -> Query ()

Push the context, entering a new one. Pushes multiple levels if n > 1.

NB. For a version which generalizes over the underlying monad, see push

pop :: Int -> Query ()

Pop the context, exiting a new one. Pops multiple levels if n > 1. It's an error to pop levels that don't exist.

NB. For a version which generalizes over the underlying monad, see pop

inNewAssertionStack :: Query a -> Query a

Run the query in a new assertion stack. That is, we push the context, run the query commands, and pop it back.

NB. For a version which generalizes over the underlying monad, see inNewAssertionStack

Higher level tactics

caseSplit :: Bool -> [(String, SBool)] -> Query (Maybe (String, SMTResult))

Search for a result via a sequence of case-splits, guided by the user. If one of the conditions lead to a satisfiable result, returns Just that result. If none of them do, returns Nothing. Note that we automatically generate a coverage case and search for it automatically as well. In that latter case, the string returned will be Coverage. The first argument controls printing progress messages See Documentation.SBV.Examples.Queries.CaseSplit for an example use case.

NB. For a version which generalizes over the underlying monad, see caseSplit

Resetting the solver state

resetAssertions :: Query ()

Reset the solver, by forgetting all the assertions. However, bindings are kept as is, as opposed to a full reset of the solver. Use this variant to clean-up the solver state while leaving the bindings intact. Pops all assertion levels. Declarations and definitions resulting from the setLogic command are unaffected. Note that SBV implicitly uses global-declarations, so bindings will remain intact.

NB. For a version which generalizes over the underlying monad, see resetAssertions

Constructing assignments

(|->) :: SymVal a => SBV a -> a -> Assignment infix 1

Make an assignment. The type Assignment is abstract, the result is typically passed to mkSMTResult:

 mkSMTResult [ a |-> 332
             , b |-> 2.3
             , c |-> True
             ]

End users should use getModel for automatically constructing models from the current solver state. However, an explicit Assignment might be handy in complex scenarios where a model needs to be created manually.

Terminating the query

mkSMTResult :: [Assignment] -> Query SMTResult

Produce the query result from an assignment.

NB. For a version which generalizes over the underlying monad, see mkSMTResult

exit :: Query ()

Exit the solver. This action will cause the solver to terminate. Needless to say, trying to communicate with the solver after issuing "exit" will simply fail.

NB. For a version which generalizes over the underlying monad, see exit

Controlling the solver behavior

ignoreExitCode :: SMTConfig -> Bool

If true, we shall ignore the exit code upon exit. Otherwise we require ExitSuccess.

timeout :: Int -> Query a -> Query a

Timeout a query action, typically a command call to the underlying SMT solver. The duration is in microseconds (1/10^6 seconds). If the duration is negative, then no timeout is imposed. When specifying long timeouts, be careful not to exceed maxBound :: Int. (On a 64 bit machine, this bound is practically infinite. But on a 32 bit machine, it corresponds to about 36 minutes!)

Semantics: The call timeout n q causes the timeout value to be applied to all interactive calls that take place as we execute the query q. That is, each call that happens during the execution of q gets a separate time-out value, as opposed to one timeout value that limits the whole query. This is typically the intended behavior. It is advisable to apply this combinator to calls that involve a single call to the solver for finer control, as opposed to an entire set of interactions. However, different use cases might call for different scenarios.

If the solver responds within the time-out specified, then we continue as usual. However, if the backend solver times-out using this mechanism, there is no telling what the state of the solver will be. Thus, we raise an error in this case.

NB. For a version which generalizes over the underlying monad, see timeout

Miscellaneous

queryDebug :: [String] -> Query ()

If verbose is True, print the message, useful for debugging messages in custom queries. Note that redirectVerbose will be respected: If a file redirection is given, the output will go to the file.

NB. For a version which generalizes over the underlying monad, see queryDebug

echo :: String -> Query ()

Echo a string. Note that the echoing is done by the solver, not by SBV.

NB. For a version which generalizes over the underlying monad, see echo

io :: IO a -> Query a

Perform an arbitrary IO action.

NB. For a version which generalizes over the underlying monad, see io

Solver options

data SMTOption

Option values that can be set in the solver, following the SMTLib specification http://smtlib.cs.uiowa.edu/language.shtml.

Note that not all solvers may support all of these!

Furthermore, SBV doesn't support the following options allowed by SMTLib.

• :interactive-mode (Deprecated in SMTLib, use ProduceAssertions instead.)
• :print-success (SBV critically needs this to be True in query mode.)
• :produce-models (SBV always sets this option so it can extract models.)
• :regular-output-channel (SBV always requires regular output to come on stdout for query purposes.)
• :global-declarations (SBV always uses global declarations since definitions are accumulative.)

Note that SetLogic and SetInfo are, strictly speaking, not SMTLib options. However, we treat it as such here uniformly, as it fits better with how options work.

Constructors

DiagnosticOutputChannel FilePath

ProduceAssertions Bool

ProduceAssignments Bool

ProduceProofs Bool

ProduceInterpolants Bool

ProduceUnsatAssumptions Bool

ProduceUnsatCores Bool

RandomSeed Integer

ReproducibleResourceLimit Integer

SMTVerbosity Integer

OptionKeyword String [String]

SetLogic Logic

SetInfo String [String]

Instances

Show SMTOption

Defined in Data.SBV.Control.Types

Methods

showsPrec :: Int -> SMTOption -> ShowS

show :: SMTOption -> String

showList :: [SMTOption] -> ShowS