Proposal to deprecate and then drop fromJust

Joachim Breitner mail at
Tue Feb 24 10:10:38 UTC 2015


Am Montag, den 23.02.2015, 21:42 -0800 schrieb Erik de Castro Lopo:
> The idea would be to deprecate fromMaybe for 7.12 and remove it
> completely later.


If it wasn’t there, I probably would not vote for adding it, but in the
interest of general stability, I believe removing this function is not
worth the effort.

Also, just removing fromMaybe when there are many other partial
functions, some in the Prelude, does not really cut it. If there was a
larger proposal „Make Haskell free of Partial Functions“, then that
would be a different thing. And I don’t think that that can be tackled
before "base" becomes an interface only that can be upgraded separately
from the compiler, with past major versions still supported... but I

Also, the argument that it is useful in scripts and in the REPL is a
valid one.


Joachim “nomeata” Breitner
  mail at joachim-breitner.de
  Jabber: nomeata at  • GPG-Key: 0xF0FBF51F
  Debian Developer: nomeata at

-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 819 bytes
Desc: This is a digitally signed message part
URL: <>

More information about the Libraries mailing list