Skip to content
Snippets Groups Projects

rec {} causes "head:empty list" exception

    • Closed Issue created by Alan Zimmerman @alanz

    Using GHC HEAD 7.11.20150116 (and before)

    Trying to load the following into ghci

    {-# LANGUAGE RecursiveDo #-}

bar :: IO ()
bar = do
  rec {}
  return ()

    results in

    > :load "/home/alanz/mysrc/github/alanz/ghc-exactprint/tests/examples/Foo.hs"
[1 of 1] Compiling Main             ( /home/alanz/mysrc/github/alanz/ghc-exactprint/tests/examples/Foo.hs, interpreted )
*** Exception: Prelude.head: empty list
>
    Trac metadata
    Trac field Value
    Version 7.11
    Type Bug
    TypeOfFailure OtherFailure
    Priority normal
    Resolution Unresolved
    Component Compiler
    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