Data.SBV.Plugin

(The sbvPlugin is hosted at http://github.com/LeventErkok/sbvPlugin. Comments, bug reports, and patches are always welcome.)

SBVPlugin: A GHC Plugin for SBV, SMT Based Verification

SBV is a library for express properties about Haskell programs and automatically proving them using SMT solvers. The SBVPlugin allows simple annotations on Haskell functions to prove them directly during GHC compilation time.

Consider the following simple program:

{-# OPTIONS_GHC -fplugin=Data.SBV.Plugin #-}

module Test where

import Data.SBV.Plugin

{-# ANN test theorem #-}
test :: Integer -> Integer -> Bool
test x y = x + y >= x - y

We have:

$ ghc -c Test.hs

[SBV] Test.hs:9:1-4 Proving "test", using Z3.
[Z3] Falsifiable. Counter-example:
  x =  0 :: Integer
  y = -1 :: Integer
[SBV] Failed. (Use option 'IgnoreFailure' to continue.)

Note that the compilation will be aborted, since the theorem doesn't hold. As shown in the hint, GHC can be instructed to continue in that case, using an annotation of the form:

{-# ANN test theorem {options = [IgnoreFailure]} #-}

The plugin should work from GHCi with no changes. Note that when run from GHCi, the plugin will behave as if the IgnoreFailure option is given on all annotations, so that failures do not stop the load process.

Entry point

plugin :: Plugin

Entry point to the plugin

Annotations

newtype SBVAnnotation

The actual annotation.

Constructors

SBV

Fields

options :: [SBVOption]

Instances

Eq SBVAnnotation

Data SBVAnnotation

sbv :: SBVAnnotation

A property annotation, using default options.

theorem :: SBVAnnotation

Synonym for sbv really, just looks cooler

Plugin options

data SBVOption

Plugin options. Note that we allow picking multiple solvers, which will all be run in parallel. If you want to run all available solvers, use the option AnySolver. The default is to error-out on failure, using the default-SMT solver picked by SBV, which is currently Z3.

Constructors

IgnoreFailure

Continue even if proof fails

Skip String

Skip the proof. Can be handy for properties that we currently do not want to focus on.

Verbose

Produce verbose output, good for debugging

Safety

Check for safety

QuickCheck

Perform quickCheck

Uninterpret

Uninterpret this binding for proof purposes

Names [String]

Use these names for the arguments; need not be exhaustive

Z3

Use Z3

Yices

Use Yices

Boolector

Use Boolector

CVC4

Use CVC4

MathSAT

Use MathSAT

ABC

Use ABC

AnySolver

Use all installed solvers

Instances

Eq SBVOption

Data SBVOption

Show SBVOption