Don't worry about supporting trailing/leading commas everywhere for now.
Have it work for records first. We can always add support in more places
later.
On Mon, Sep 22, 2014 at 9:07 PM, Simon Peyton Jones
I’m all for it. To progress it you need to
· open a Trac ticket,
· start a wiki page to describe the design specifically (e.g give all the changed syntax rules)
· have a language extension TrailingCommas (or something) to enable the extension
· perhaps suggest switching on the extension if the program parses with it, but fails without
· develop a patch
Easy really! I doubt it’s controversial.
Simon
*From:* ghc-devs [mailto:ghc-devs-bounces@haskell.org] *On Behalf Of *Johan Tibell *Sent:* 22 September 2014 14:28 *To:* Alexander Berntsen *Cc:* ghc-devs@haskell.org *Subject:* Re: Permitting trailing commas for record syntax ADT declarations
+1
I think this makes sense and we should allow trailing commas wherever the syntax allows it without adding ambiguity (e.g. tuple sections prevent trailing commas for tuple declarations.)
P.S. Last time we tried to discuss something like this (on libraries@ I believe) the whole discussion devolved into a "lets rewrite all of Haskell". Lets not do that here. Thanks!