Skip to content
Snippets Groups Projects

GHC leaks GHC.Prim.~# into type

    • Closed Issue created by Icelandjack @Icelandjack 
    data A a where
  X :: A [xxx]

pattern X' = X

    the inferred type of which is

    >>> :info X'
pattern X' :: () => t GHC.Prim.~# [xxx] => A t

    Casts use unlifted equality as I understand it, but lifted would present a nicer UI:

    pattern X' :: () => t ~> [xxx] => A t
pattern X' = X

    In my own code this means I get the following monster

    pattern MkArr :: () => (GetTy a, GetTy b, GetTy t,
                        a GHC.Prim.~# 'Sca ('Number 'I32), b GHC.Prim.~# 'Sca a1,
                        t GHC.Prim.~# 'Arr a1, GetSca a1) => Exp a -> Id -> Exp b -> Exp t
    Trac metadata
    Trac field Value
    Version 7.10.3
    Type FeatureRequest
    TypeOfFailure OtherFailure
    Priority normal
    Resolution Unresolved
    Component Compiler (Type checker)
    Test case
    Differential revisions
    BlockedBy
    Related
    Blocking
    CC
    Operating system
    Architecture
    To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information

    Child items 0

    • No child items are currently assigned. Use child items to break down this issue into smaller parts.

    Activity

    Please register or sign in to reply