Re: Misleading strictness annotations in Data.List.NonEmpty

8 Jan 2021

      Thanks, will do.

On January 8, 2021 5:07:25 PM UTC, David Feuer  wrote:
...
The first one. Neither twiddles nor bangs are useful or add clarity.
On Fri, Jan 8, 2021, 11:53 AM Keith  wrote:
...
Currently:
head ~(a :| _) = a
tail ~(_ :| as) = as
But head and tail are both strict. At best the '~'s have no effect.
Should I open a PR to change it to
head (a :| _) = a
tail (_ :| as) = as
or maybe even more clearly
head !(a :l _) = a
tail !(_ :| as) = as
?
--Keith
Sent from my phone with K-9 Mail.
Good to know! Wasn't aware that that was in the works.

And sorry for accidentally threading this onto something unrelated.

-- Keith
Sent from my phone with K-9 Mail.

On January 8, 2021 5:13:31 PM UTC, Henning Thielemann  wrote:
...
On Fri, 8 Jan 2021, Keith wrote:
...
Currently:
head ~(a :| _) = a
tail ~(_ :| as) = as
But head and tail are both strict. At best the '~'s have no effect.
Should I open a PR to change it to
head (a :| _) = a
tail (_ :| as) = as
or maybe even more clearly
head !(a :l _) = a
tail !(_ :| as) = as
?
The last one would trigger the "redundant bang pattern" warning that is 
going to be implemented/released:
   https://gitlab.haskell.org/ghc/ghc/issues/17340