Call to arms: lambda-case is stuck and needs your help

Wolfgang Jeltsch g9ks157k at
Tue Jul 10 13:53:23 CEST 2012

Am Dienstag, den 10.07.2012, 06:53 +0000 schrieb Simon Peyton-Jones:
> > I strongly favor a solution where lambda-case expressions start with \,
> > because this can be generalized to proc expressions from arrow syntax
> > simply by replacing the \ with proc.
>  […]
> I think it's very helpful if lambdas start with a lambda, which to me
> suggests \case.  I'm not keen on \of; "case" says "case analysis" more
> clearly. But you presumably do not want \proc, because proc is the
> lambda. So that would leave use with "\case" and "proc of" as the two
> constructs.  Perhaps the lesser of the evils, but a bit inconsistent.

If we use \case for functions, we should use proc case for arrows;
if we use \of for functions, we should use proc of for arrows.

By the way, is proc a layout herald already?

Best wishes,

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