Cryptol.TypeCheck.Monad

Documentation

data InferInput

Information needed for type inference.

Constructors

InferInput

Fields

• inpRange :: Range

  Location of program source

• inpVars :: Map Name Schema

  Variables that are in scope

• inpTSyns :: Map Name TySyn

  Type synonyms that are in scope

• inpNominalTypes :: Map Name NominalType

  Nominal types in scope

• inpSignatures :: !(Map Name ModParamNames)

  Signatures in scope

• inpTopModules :: ModName -> Maybe (ModuleG (), IfaceG ())
• inpTopSignatures :: ModName -> Maybe ModParamNames
• inpParams :: !ModParamNames
• inpNameSeeds :: NameSeeds

  Private state of type-checker

• inpMonoBinds :: Bool

  Should local bindings without signatures be monomorphized?

• inpCallStacks :: Bool

  Are we tracking call stacks?

• inpSearchPath :: [FilePath]

  Where to look for Cryptol theory file.

• inpPrimNames :: !PrimMap

  This is used when the type-checker needs to refer to a predefined identifier (e.g., number).

• inpSupply :: !Supply

  The supply for fresh name generation

• inpSolver :: Solver

  Solver connection for typechecking

data InferOutput a

The results of type inference.

Constructors

InferFailed NameMap [(Range, Warning)] [(Range, Error)]

We found some errors

InferOK NameMap [(Range, Warning)] NameSeeds Supply a

Type inference was successful.

Instances

Show a => Show (InferOutput a)

Defined in Cryptol.TypeCheck.Monad

Methods

showsPrec :: Int -> InferOutput a -> ShowS

show :: InferOutput a -> String

showList :: [InferOutput a] -> ShowS

data NameSeeds

This is used for generating various names.

Constructors

NameSeeds

Fields

• seedTVar :: !Int
• seedGoal :: !Int

Instances

Generic NameSeeds

Defined in Cryptol.TypeCheck.Monad

Associated Types

type Rep NameSeeds :: Type -> Type

Methods

from :: NameSeeds -> Rep NameSeeds x

to :: Rep NameSeeds x -> NameSeeds

Show NameSeeds

Defined in Cryptol.TypeCheck.Monad

Methods

showsPrec :: Int -> NameSeeds -> ShowS

show :: NameSeeds -> String

showList :: [NameSeeds] -> ShowS

NFData NameSeeds

Defined in Cryptol.TypeCheck.Monad

Methods

rnf :: NameSeeds -> ()

type Rep NameSeeds

Defined in Cryptol.TypeCheck.Monad

type Rep NameSeeds = D1 ('MetaData "NameSeeds" "Cryptol.TypeCheck.Monad" "cryptol-3.3.0-7OIQa8lMv7L2xoAlM9JEI6" 'False) (C1 ('MetaCons "NameSeeds" 'PrefixI 'True) (S1 ('MetaSel ('Just "seedTVar") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 Int) :*: S1 ('MetaSel ('Just "seedGoal") 'NoSourceUnpackedness 'SourceStrict 'DecidedStrict) (Rec0 Int)))

newtype InferM a

Constructors

IM

Fields

• unIM :: ReaderT RO (StateT RW (ExceptionT [(Range, Error)] IO)) a

Instances

MonadFail InferM

Defined in Cryptol.TypeCheck.Monad

Methods

fail :: String -> InferM a

MonadFix InferM

Defined in Cryptol.TypeCheck.Monad

Methods

mfix :: (a -> InferM a) -> InferM a

Applicative InferM

Defined in Cryptol.TypeCheck.Monad

Methods

pure :: a -> InferM a

(<*>) :: InferM (a -> b) -> InferM a -> InferM b

liftA2 :: (a -> b -> c) -> InferM a -> InferM b -> InferM c

(*>) :: InferM a -> InferM b -> InferM b

(<*) :: InferM a -> InferM b -> InferM a

Functor InferM

Defined in Cryptol.TypeCheck.Monad

Methods

fmap :: (a -> b) -> InferM a -> InferM b

(<$) :: a -> InferM b -> InferM a

Monad InferM

Defined in Cryptol.TypeCheck.Monad

Methods

(>>=) :: InferM a -> (a -> InferM b) -> InferM b

(>>) :: InferM a -> InferM b -> InferM b

return :: a -> InferM a

FreshM InferM

Defined in Cryptol.TypeCheck.Monad

Methods

liftSupply :: (Supply -> (a, Supply)) -> InferM a

data RW

Read-write component of the monad.

Constructors

RW

Fields

• iErrors :: ![(Range, Error)]

  Collected errors

• iWarnings :: ![(Range, Warning)]

  Collected warnings

• iSubst :: !Subst

  Accumulated substitution

• iExistTVars :: [Map Name Type]

  These keeps track of what existential type variables are available. When we start checking a function, we push a new scope for its arguments, and we pop it when we are done checking the function body. The front element of the list is the current scope, which is the only thing that will be modified, as follows. When we encounter a existential type variable: 1. we look in all scopes to see if it is already defined. 2. if it was not defined, we create a fresh type variable, and we add it to the current scope. 3. it is an error if we encounter an existential variable but we have no current scope.

• iSolvedHas :: Map Int HasGoalSln

  Selector constraints that have been solved (ref. iSolvedSelectorsLazy)

• iNameSeeds :: !NameSeeds
• iCts :: !Goals

  Ordinary constraints

• iHasCts :: ![[HasGoal]]

  Tuple/record projection constraints. These are separate from the other constraints because solving them results in actual elaboration of the term, indicating how to do the projection. The modification of the term is done using lazyness, by looking up a thunk ahead of time (iSolvedHasLazy in RO), which is filled in when the constrait is solved (iSolvedHas). See also selectorScope.

• iScope :: ![ModuleG ScopeName]

  Nested scopes we are currently checking, most nested first. These are basically partially built modules.

• iBindTypes :: !(Map Name Schema)

  Types of variables that we know about. We don't worry about scoping here because we assume the bindings all have different names.

• iSupply :: !Supply

data RO

Read-only component of the monad.

Constructors

RO

Fields

• iRange :: Range

  Source code being analysed

• iVars :: Map Name VarType

  Type of variable that are in scope These are only parameters vars that are in recursive component we are checking at the moment. If a var is not there, keep looking in the iScope

• iTVars :: [TParam]

  Type variable that are in scope

• iExtModules :: ModName -> Maybe (ModuleG (), IfaceG ())

  An exteral top-level module. We need the actual module when we instantiate functors, because currently the type-checker desugars such modules.

• iExtSignatures :: ModName -> Maybe ModParamNames

  External top-level signatures.

• iExtScope :: ModuleG ScopeName

  These are things we know about, but are not part of the modules we are currently constructing. XXX: this sould probably be an interface NOTE: External functors should be looked up in iExtModules and not here, as they may be top-level modules.

• iSolvedHasLazy :: Map Int HasGoalSln

  NOTE: This field is lazy in an important way! It is the final version of iSolvedHas in RW, and the two are tied together through recursion. The field is here so that we can look thing up before they are defined, which is OK because we don't need to know the results until everything is done.

• iMonoBinds :: Bool

  When this flag is set to true, bindings that lack signatures in where-blocks will never be generalized. Bindings with type signatures, and all bindings at top level are unaffected.

• iCallStacks :: Bool

  When this flag is true, retain source location information in typechecked terms

• iSolver :: Solver
• iPrimNames :: !PrimMap
• iSolveCounter :: !(IORef Int)

data ScopeName

Constructors

ExternalScope

LocalScope

SubModule Name

SignatureScope Name (Maybe Text)

The Text is docs

TopSignatureScope ModName

MTopModule ModName

newtype KindM a

Constructors

KM

Fields

• unKM :: ReaderT KRO (StateT KRW InferM) a

Instances

MonadFail KindM

Defined in Cryptol.TypeCheck.Monad

Methods

fail :: String -> KindM a

Applicative KindM

Defined in Cryptol.TypeCheck.Monad

Methods

pure :: a -> KindM a

(<*>) :: KindM (a -> b) -> KindM a -> KindM b

liftA2 :: (a -> b -> c) -> KindM a -> KindM b -> KindM c

(*>) :: KindM a -> KindM b -> KindM b

(<*) :: KindM a -> KindM b -> KindM a

Functor KindM

Defined in Cryptol.TypeCheck.Monad

Methods

fmap :: (a -> b) -> KindM a -> KindM b

(<$) :: a -> KindM b -> KindM a

Monad KindM

Defined in Cryptol.TypeCheck.Monad

Methods

(>>=) :: KindM a -> (a -> KindM b) -> KindM b

(>>) :: KindM a -> KindM b -> KindM b

return :: a -> KindM a

data KRO

Constructors

KRO

Fields

• lazyTParams :: Map Name TParam

  lazy map, with tparams.

• allowWild :: AllowWildCards

  are type-wild cards allowed?

data KRW

Constructors

KRW

Fields

• typeParams :: Map Name Kind

  kinds of (known) vars.

• kCtrs :: [(ConstraintSource, [Prop])]

data AllowWildCards

Do we allow wild cards in the given context.

Constructors

AllowWildCards

NoWildCards

data LkpTyVar

This is what's returned when we lookup variables during kind checking.

Constructors

TLocalVar TParam (Maybe Kind)

Locally bound variable.

TOuterVar TParam

An outer binding.

newName :: (NameSeeds -> (a, NameSeeds)) -> InferM a

inRange :: Range -> InferM a -> InferM a

The monadic computation is about the given range of source code. This is useful for error reporting.

newTVar :: TypeSource -> Kind -> InferM TVar

Generate a new free type variable.

io :: IO a -> InferM a

inNewScope :: InferM a -> InferM a

Perform the given computation in a new scope (i.e., the subcomputation may use existential type variables). This is a different kind of scope from the nested modules one.

getScope :: Semigroup a => (ModuleG ScopeName -> a) -> InferM a

Get an environment combining all nested scopes.

getPrimMap :: InferM PrimMap

Retrieve the mapping between identifiers and declarations in the prelude.

lookupModule :: ImpName Name -> InferM (IfaceG ())

Get information about the things defined in the module. Note that, in general, the interface may contain *more* than just the definitions in the module, however the ifNames should indicate which ones are part of the module.

nameSeeds :: NameSeeds

The initial seeds, used when checking a fresh program. XXX: why does this start at 10?

runInferM :: TVars a => InferInput -> InferM a -> IO (InferOutput a)

lookupVar :: Name -> InferM VarType

Lookup the type of a variable.

newLocalScope :: InferM ()

endLocalScope :: InferM ([DeclGroup], Map Name TySyn)

withTParams :: [TParam] -> InferM a -> InferM a

unify :: TypeWithSource -> Type -> InferM [Prop]

Record that the two types should be syntactically equal.

newGoals :: ConstraintSource -> [Prop] -> InferM ()

Record some constraints that need to be solved. The string explains where the constraints came from.

newType :: TypeSource -> Kind -> InferM Type

Generate an unknown type. The doc is a note about what is this type about.

applySubst :: TVars t => t -> InferM t

Apply the accumulated substitution to something with free type variables.

solveHasGoal :: Int -> HasGoalSln -> InferM ()

Specify the solution (Expr -> Expr) for the given constraint (Int).

newLocalName :: Namespace -> Ident -> InferM Name

Generate a fresh variable name to be used in a local binding.

getCallStacks :: InferM Bool

curRange :: InferM Range

This is the current range that we are working on.

recordError :: Error -> InferM ()

Report an error.

recordWarning :: Warning -> InferM ()

bumpCounter :: InferM ()

selectorScope :: InferM a -> InferM a

This introduces a new "selector scope" which is currently a module. I think that it might be possible to have selectors scopes be groups of recursive declarations instead, as we are not going to learn anything additional once we are done with the recursive group that generated the selectors constraints. We do it at the module level because this allows us to report more errors at once.

A selector scope does the following: * Keep track of the Has constraints generated in this scope * Keep track of the solutions for discharged selector constraints: - this uses a laziness trick where we build up a map containing the solutions for the Has constraints in the state - the *final* value for this map (i.e., at the value the end of the scope) is passed in as thunk in the reader component of the moment - as we type check expressions when we need the solution for a Has constraint we look it up from the reader environment; note that since the map is not yet built up we just get back a thunk, so we have to be carefule to not force it until *after* we've solved the goals - all of this happens in the `rec` block below * At the end of a selector scope we make sure that all Has constraints were discharged. If not, we *abort* further type checking. The reason for aborting rather than just recording an error is that the expression which produce contains thunks that will lead to non-termination if forced, and some type-checking operations (e.g., instantiation a functor) require us to traverse the expressions.

abortIfErrors :: InferM ()

If there are any recoded errors than abort firther type-checking.

inRangeMb :: Maybe Range -> InferM a -> InferM a

recordErrorLoc :: Maybe Range -> Error -> InferM ()

Report an error.

getSolver :: InferM Solver

newGoal :: ConstraintSource -> Prop -> InferM Goal

addGoals :: [Goal] -> InferM ()

Add a bunch of goals that need solving.

getGoals :: InferM [Goal]

The constraints are removed, and returned to the caller. The substitution IS applied to them.

simpGoals :: [Goal] -> InferM [Goal]

collectGoals :: InferM a -> InferM (a, [Goal])

Collect the goals emitted by the given sub-computation. Does not emit any new goals.

simpGoal :: Goal -> InferM [Goal]

newHasGoal :: Selector -> Type -> Type -> InferM HasGoalSln

Record a constraint that when we select from the first type, we should get a value of the second type. The returned function should be used to wrap the expression from which we are selecting (i.e., the record or tuple). Plese note that the resulting expression should not be forced before the constraint is solved.

newGoalName :: InferM Int

Generate a new name for a goal.

addHasGoal :: HasGoal -> InferM ()

Add a previously generated Has constraint

getHasGoals :: InferM [HasGoal]

Get the Has constraints. Each of this should either be solved, or added back using addHasGoal.

newTVar' :: TypeSource -> Set TParam -> Kind -> InferM TVar

Generate a new free type variable that depends on these additional type parameters.

getBoundInScope :: InferM (Set TParam)

Return the keys of the bound variables that are in scope.

checkParamKind :: TParam -> TPFlavor -> Kind -> InferM ()

Check that the given "flavor" of parameter is allowed to have the given type, and raise an error if not

newTParam :: TParam Name -> TPFlavor -> Kind -> InferM TParam

Generate a new free type variable.

freshTParam :: (Name -> TPFlavor) -> TParam -> InferM TParam

Generate a new version of a type parameter. We use this when instantiating module parameters (the "backtick" imports)

extendSubst :: Subst -> InferM ()

Add to the accumulated substitution, checking that the datatype invariant for Subst is maintained.

getSubst :: InferM Subst

Get the substitution that we have accumulated so far.

applySubstPreds :: [Prop] -> InferM [Prop]

applySubstGoals :: [Goal] -> InferM [Goal]

varsWithAsmps :: InferM (Set TVar)

Variables that are either mentioned in the environment or in a selector constraint.

lookupTParam :: Name -> InferM (Maybe TParam)

Lookup a type variable. Return Nothing if there is no such variable in scope, in which case we must be dealing with a type constant.

lookupTSyn :: Name -> InferM (Maybe TySyn)

Lookup the definition of a type synonym.

getTSyns :: InferM (Map Name TySyn)

Returns the type synonyms that are currently in scope.

lookupNominal :: Name -> InferM (Maybe NominalType)

Lookup the definition of a nominal type

getNominalTypes :: InferM (Map Name NominalType)

Returns the nominal type declarations that are in scope.

lookupParamType :: Name -> InferM (Maybe ModTParam)

Lookup the kind of a parameter type

getParamTypes :: InferM (Map Name ModTParam)

Returns the abstract function declarations

lookupSignature :: ImpName Name -> InferM ModParamNames

getSignatures :: InferM (Map Name ModParamNames)

lookupTopModule :: ModName -> InferM (Maybe (ModuleG (), IfaceG ()))

Lookup an external (i.e., previously loaded) top module.

lookupFunctor :: ImpName Name -> InferM (ModuleG ())

getCurDecls :: InferM (ModuleG ())

lookupModParam :: Ident -> InferM (Maybe ModParam)

existVar :: Name -> Kind -> InferM Type

Check if we already have a name for this existential type variable and, if so, return the definition. If not, try to create a new definition, if this is allowed. If not, returns nothing.

getParamConstraints :: InferM [Located Prop]

Constraints on the module's parameters.

getTVars :: InferM (Set Name)

Get the set of bound type variables that are in scope.

getMonoBinds :: InferM Bool

Retrieve the value of the `mono-binds` option.

checkTShadowing :: String -> Name -> InferM ()

We disallow shadowing between type synonyms and type variables because it is confusing. As a bonus, in the implementation we don't need to worry about where we lookup things (i.e., in the variable or type synonym environment.

withTParam :: TParam -> InferM a -> InferM a

The sub-computation is performed with the given type parameter in scope.

newScope :: ScopeName -> InferM ()

Execute the given computation in a new top scope. The sub-computation would typically be validating a module.

newSignatureScope :: Name -> Maybe Text -> InferM ()

updScope :: (ModuleG ScopeName -> ModuleG ScopeName) -> InferM ()

Update the current scope (first in the list). Assumes there is one.

newTopSignatureScope :: ModName -> InferM ()

newSubmoduleScope :: Name -> [Text] -> ExportSpec Name -> NamingEnv -> InferM ()

Start a new submodule scope. The imports and exports are just used to initialize an empty module. As we type check declarations they are added to this module's scope.

newModuleScope :: [Text] -> ModName -> ExportSpec Name -> NamingEnv -> InferM ()

endSubmodule :: InferM ()

endModule :: InferM TCTopEntity

endSignature :: InferM ()

endTopSignature :: InferM TCTopEntity

addDecls :: DeclGroup -> InferM ()

addTySyn :: TySyn -> InferM ()

The sub-computation is performed with the given type-synonym in scope.

addNominal :: NominalType -> InferM ()

addParamType :: ModTParam -> InferM ()

addSignatures :: Map Name ModParamNames -> InferM ()

addSubmodules :: Map Name Submodule -> InferM ()

addFunctors :: Map Name (ModuleG Name) -> InferM ()

setNested :: Set Name -> InferM ()

addParamFun :: ModVParam -> InferM ()

The sub-computation is performed with the given abstract function in scope.

addParameterConstraints :: [Located Prop] -> InferM ()

Add some assumptions for an entire module

addModParam :: ModParam -> InferM ()

withVarType :: Name -> VarType -> InferM a -> InferM a

The sub-computation is performed with the given variable in scope.

withVarTypes :: [(Name, VarType)] -> InferM a -> InferM a

withVar :: Name -> Schema -> InferM a -> InferM a

withMonoType :: (Name, Located Type) -> InferM a -> InferM a

The sub-computation is performed with the given variables in scope.

withMonoTypes :: Map Name (Located Type) -> InferM a -> InferM a

The sub-computation is performed with the given variables in scope.

runKindM

Arguments

:: AllowWildCards

-> [(Name, Maybe Kind, TParam)]

See comment

-> KindM a

-> InferM (a, Map Name Kind, [(ConstraintSource, [Prop])])

The arguments to this function are as follows:

(type param. name, kind signature (opt.), type parameter)

The type parameter is just a thunk that we should not force. The reason is that the parameter depends on the kind that we are in the process of computing.

As a result we return the value of the sub-computation and the computed kinds of the type parameters.

kLookupTyVar :: Name -> KindM (Maybe LkpTyVar)

Check if a name refers to a type variable.

kWildOK :: KindM AllowWildCards

Are type wild-cards OK in this context?

kRecordError :: Error -> KindM ()

Reports an error.

kInInferM :: InferM a -> KindM a

kRecordWarning :: Warning -> KindM ()

kIO :: IO a -> KindM a

kNewType :: TypeSource -> Kind -> KindM Type

Generate a fresh unification variable of the given kind. NOTE: We do not simplify these, because we end up with bottom. See hs XXX: Perhaps we can avoid the recursion?

kLookupTSyn :: Name -> KindM (Maybe TySyn)

Lookup the definition of a type synonym.

kLookupNominal :: Name -> KindM (Maybe NominalType)

Lookup the definition of a nominal type.

kLookupParamType :: Name -> KindM (Maybe ModTParam)

kExistTVar :: Name -> Kind -> KindM Type

kInstantiateT :: Type -> [(TParam, Type)] -> KindM Type

Replace the given bound variables with concrete types.

kSetKind :: Name -> Kind -> KindM ()

Record the kind for a local type variable. This assumes that we already checked that there was no other valid kind for the variable (if there was one, it gets over-written).

kInRange :: Range -> KindM a -> KindM a

The sub-computation is about the given range of the source code.

kNewGoals :: ConstraintSource -> [Prop] -> KindM ()

module Cryptol.TypeCheck.InferTypes