DDC.Core.Transform.Rewrite.Env

Documentation

data RewriteEnv a n

A summary of the environment that we perform a rewrite in.

As we decend into the program looking for expressions to rewrite, we keep track of what information as been defined in the environment in a RewriteEnv.

When we go under an anonymous binder then we push a new outermost list instead of lifting every element on the environment eagerly.

Instances

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

Methods

(==) :: RewriteEnv a n -> RewriteEnv a n -> Bool

(/=) :: RewriteEnv a n -> RewriteEnv a n -> Bool

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

Methods

showsPrec :: Int -> RewriteEnv a n -> ShowS

show :: RewriteEnv a n -> String

showList :: [RewriteEnv a n] -> ShowS

empty :: RewriteEnv a n

An empty environment.

extend :: Ord n => Bind n -> RewriteEnv a n -> RewriteEnv a n

Extend an environment with some lambda-bound binder (XLam) Might be a witness. Don't count if it's a region.

extendLets :: Ord n => Lets a n -> RewriteEnv a n -> RewriteEnv a n

Extend an environment with the variables bount by these let-bindings.

If it's a letregion, remember the region's name and any witnesses.

containsRegion :: Ord n => Bound n -> RewriteEnv a n -> Bool

Check whether an environment contains the given region, bound by a letregion.

containsWitness :: Ord n => Type n -> RewriteEnv a n -> Bool

Check if the witness map in the given environment.

getWitnesses :: Ord n => RewriteEnv a n -> [Type n]

Get a list of all the witness types in an environment, normalising their indices.

insertDef :: Bind n -> Maybe (Exp a n) -> RewriteEnv a n -> RewriteEnv a n

Insert a rewrite definition into the environment.

getDef :: (Ord n, MapBoundX (Exp a) n) => Bound n -> RewriteEnv a n -> Maybe (Exp a n)

Lookup the definition of some let-bound variable from the environment.

hasDef :: (Ord n, MapBoundX (Exp a) n) => Bound n -> RewriteEnv a n -> Bool

lift :: Bind n -> RewriteEnv a n -> RewriteEnv a n

Raise all elements in witness map if binder is anonymous. Only call with type binders: ie XLAM, not XLam

liftValue :: Bind n -> RewriteEnv a n -> RewriteEnv a n

Raise all elements in definitions map if binder is anonymous Use for *value* binders, not type binders.