Some arguments to functions (types in particular) will not be used in the body. Wouldn't it be useful if these wasn't passed around at all? Fear not, we here perform some analysis and try to remove as many of these occurences as possible.

We employ the worker/wrapper transform, so if f x1 .. xn = e and we notice that some is not needed we create: f' xj .. xk = e [xi := unit] and f x1 .. xn = f' xj .. xk. i.e we erase them in f' and replace by unit, and the original f function calls the new f'. The idea is that f should be inlined and then peace on earth.

- isIrr :: Relevance -> Bool
- isRel :: Relevance -> Bool
- (||-) :: Relevance -> Relevance -> Relevance
- (&&-) :: Relevance -> Relevance -> Relevance
- data ErasureState = ErasureState {}
- type Erasure = StateT ErasureState
- erasure :: [Fun] -> Compile TCM [Fun]
- removeUnused :: Map Var [Relevance] -> Expr -> Expr
- initiate :: Fun -> Erasure (Compile TCM) ()
- initialRels :: Type -> Relevance -> [Relevance]
- ignoreForced :: Relevance -> Bool
- relevant :: (Functor m, Monad m) => Var -> Expr -> Erasure m Relevance
- step :: Integer -> Erasure (Compile TCM) (Map Var [Relevance])
- diff :: (Ord k, Eq a) => Map k a -> Map k a -> [(k, (a, a))]

# Documentation

type Erasure = StateT ErasureStateSource

initialRels :: Type -> Relevance -> [Relevance]Source

ignoreForced :: Relevance -> BoolSource

relevant :: (Functor m, Monad m) => Var -> Expr -> Erasure m RelevanceSource

Calculate if a variable is relevant in an expression