ddc-core-0.4.3.1: Disciplined Disciple Compiler core language and type checker.

DDC.Type.Env

Description

Type environments.

An environment contains the types named bound variables, named primitives, and a deBruijn stack for anonymous variables.

Synopsis

Documentation

data Env n Source #

A type environment.

Constructors

 Env FieldsenvMap :: !(Map n (Type n))Types of named binders.envStack :: ![Type n]Types of anonymous deBruijn binders.envStackLength :: !IntThe length of the above stack.envPrimFun :: !(n -> Maybe (Type n))Types of baked in, primitive names.

type SuperEnv n = Env n Source #

type KindEnv n = Env n Source #

type TypeEnv n = Env n Source #

Construction

An empty environment.

singleton :: Ord n => Bind n -> Env n Source #

Construct a singleton type environment.

extend :: Ord n => Bind n -> Env n -> Env n Source #

Extend an environment with a new binding. Replaces bindings with the same name already in the environment.

extends :: Ord n => [Bind n] -> Env n -> Env n Source #

Extend an environment with a list of new bindings. Replaces bindings with the same name already in the environment.

union :: Ord n => Env n -> Env n -> Env n Source #

Combine two environments. If both environments have a binding with the same name, then the one in the second environment takes preference.

unions :: Ord n => [Env n] -> Env n Source #

Combine multiple environments, with the latter ones taking preference.

Conversion

fromList :: Ord n => [Bind n] -> Env n Source #

Convert a list of Binds to an environment.

fromListNT :: Ord n => [(n, Type n)] -> Env n Source #

Convert a list of name and types into an environment

fromTypeMap :: Map n (Type n) -> Env n Source #

Convert a map of names to types to a environment.

Projections

depth :: Env n -> Int Source #

Yield the total depth of the deBruijn stack.

member :: Ord n => Bound n -> Env n -> Bool Source #

Check whether a bound variable is present in an environment.

memberBind :: Ord n => Bind n -> Env n -> Bool Source #

Check whether a binder is already present in the an environment. This can only return True for named binders, not anonymous or primitive ones.

lookup :: Ord n => Bound n -> Env n -> Maybe (Type n) Source #

Lookup a bound variable from an environment.

lookupName :: Ord n => n -> Env n -> Maybe (Type n) Source #

Lookup a bound name from an environment.

Primitives

setPrimFun :: (n -> Maybe (Type n)) -> Env n -> Env n Source #

Set the function that knows the types of primitive things.

isPrim :: Env n -> n -> Bool Source #

Check if the type of a name is defined by the envPrimFun.

Lifting

lift :: Ord n => Int -> Env n -> Env n Source #

Lift all free deBruijn indices in the environment by the given number of steps.