DDC.Core.Exp.Annot.Exp

Core language AST that includes an annotation on every node of an expression.

This is the default representation for Disciple Core, and should be preferred over the Simple version of the AST in most cases.

• Local transformations on this AST should propagate the annotations in a way that would make sense if they were source position identifiers that tracked the provenance of each code snippet. If the specific annotations attached to the AST would not make sense after such a transformation, then the client should erase them to () beforehand using the reannotate transform.
• Global transformations that drastically change the provenance of code snippets should accept an AST with an arbitrary annotation type, but produce one with the annotations set to ().

Documentation

module DDC.Type.Exp

Expressions

data Exp a n

Well-typed expressions have types of kind Data.

Constructors

XVar !a !(Bound n)

Value variable or primitive operation.

XCon !a !(DaCon n)

Data constructor or literal.

XLAM !a !(Bind n) !(Exp a n)

Type abstraction (level-1).

XLam !a !(Bind n) !(Exp a n)

Value and Witness abstraction (level-0).

XApp !a !(Exp a n) !(Exp a n)

Application.

XLet !a !(Lets a n) !(Exp a n)

Possibly recursive bindings.

XCase !a !(Exp a n) ![Alt a n]

Case branching.

XCast !a !(Cast a n) !(Exp a n)

Type cast.

XType !a !(Type n)

Type can appear as the argument of an application.

XWitness !a !(Witness a n)

Witness can appear as the argument of an application.

Instances

Reannotate Exp

Complies Exp

SubstituteWX Exp

SubstituteXX Exp

Annotate Exp Exp

Deannotate Exp Exp

SpreadX (Exp a)

SupportX (Exp a)

SubstituteTX (Exp a)

MapBoundX (Exp a) n

(Eq a, Eq n) => Eq (Exp a n)

(Show a, Show n) => Show (Exp a n)

(NFData a, NFData n) => NFData (Exp a n)

data PrettyMode (Exp a n) = PrettyModeExp {

• modeExpLets :: PrettyMode (Lets a n)
• modeExpAlt :: PrettyMode (Alt a n)
• modeExpVarTypes :: Bool
• modeExpConTypes :: Bool
• modeExpUseLetCase :: Bool

}

data Lets a n

Possibly recursive bindings.

Constructors

LLet !(Bind n) !(Exp a n)

Non-recursive expression binding.

LRec ![(Bind n, Exp a n)]

Recursive binding of lambda abstractions.

LPrivate ![Bind n] !(Maybe (Type n)) ![Bind n]

Bind a private region variable, and witnesses to its properties.

Instances

Reannotate Lets

Annotate Lets Lets

Deannotate Lets Lets

SpreadX (Lets a)

SupportX (Lets a)

(Eq a, Eq n) => Eq (Lets a n)

(Show a, Show n) => Show (Lets a n)

(NFData a, NFData n) => NFData (Lets a n)

data PrettyMode (Lets a n) = PrettyModeLets {

• modeLetsExp :: PrettyMode (Exp a n)
• modeLetsSuppressTypes :: Bool

}

data Alt a n

Case alternatives.

Constructors

AAlt !(Pat n) !(Exp a n)

Instances

Reannotate Alt

Complies Alt

SubstituteWX Alt

SubstituteXX Alt

Annotate Alt Alt

Deannotate Alt Alt

SpreadX (Alt a)

SupportX (Alt a)

SubstituteTX (Alt a)

MapBoundX (Alt a) n

(Eq a, Eq n) => Eq (Alt a n)

(Show a, Show n) => Show (Alt a n)

(NFData a, NFData n) => NFData (Alt a n)

data PrettyMode (Alt a n) = PrettyModeAlt {

• modeAltExp :: PrettyMode (Exp a n)

}

data Pat n

Pattern matching.

Constructors

PDefault

The default pattern always succeeds.

PData !(DaCon n) ![Bind n]

Match a data constructor and bind its arguments.

Instances

SpreadX Pat

Eq n => Eq (Pat n)

Show n => Show (Pat n)

NFData n => NFData (Pat n)

data Cast a n

Type casts.

Constructors

CastWeakenEffect !(Effect n)

Weaken the effect of an expression. The given effect is added to the effect of the body.

CastPurify !(Witness a n)

Purify the effect (action) of an expression.

CastBox

Box up a computation, capturing its effects in the S computation type.

CastRun

Run a computation, releasing its effects into the environment.

Instances

Reannotate Cast

SubstituteWX Cast

SubstituteXX Cast

Annotate Cast Cast

Deannotate Cast Cast

SpreadX (Cast a)

SupportX (Cast a)

SubstituteTX (Cast a)

MapBoundX (Cast a) n

(Eq a, Eq n) => Eq (Cast a n)

(Show a, Show n) => Show (Cast a n)

(NFData a, NFData n) => NFData (Cast a n)

Witnesses

data Witness a n

When a witness exists in the program it guarantees that a certain property of the program is true.

Constructors

WVar a !(Bound n)

Witness variable.

WCon a !(WiCon n)

Witness constructor.

WApp a !(Witness a n) !(Witness a n)

Witness application.

WType a !(Type n)

Type can appear as the argument of an application.

Instances

Reannotate Witness

SubstituteWX Witness

Annotate Witness Witness

Deannotate Witness Witness

SpreadX (Witness a)

SupportX (Witness a)

SubstituteTX (Witness a)

MapBoundX (Witness a) n

(Eq a, Eq n) => Eq (Witness a n)

(Show a, Show n) => Show (Witness a n)

(NFData a, NFData n) => NFData (Witness a n)

Data Constructors

data DaCon n

Data constructors.

Constructors

DaConUnit

Baked in unit data constructor.

DaConPrim

Primitive data constructor used for literals and baked-in constructors.

The type of the constructor needs to be attached to handle the case where there are too many constructors in the data type to list, like for Int literals. In this case we determine what data type it belongs to from the attached type of the data constructor.

Fields

daConName :: !n

Name of the data constructor.

daConType :: !(Type n)

Type of the data constructor.

DaConBound

Data constructor that has a data type declaration.

Fields

daConName :: !n

Name of the data constructor.

Instances

SpreadX DaCon

Eq n => Eq (DaCon n)

Show n => Show (DaCon n)

NFData n => NFData (DaCon n)

Witness Constructors

data WiCon n

Witness constructors.

Constructors

WiConBound !(Bound n) !(Type n)

Witness constructors defined in the environment. In the interpreter we use this to hold runtime capabilities. The attached type must be closed.

Instances

SpreadX WiCon

Eq n => Eq (WiCon n)

Show n => Show (WiCon n)

NFData n => NFData (WiCon n)