Call to arms: lambdacase is stuck and needs your help
Simon PeytonJones
simonpj at microsoft.com
Tue Jul 10 08:53:27 CEST 2012
 I strongly favor a solution where lambdacase expressions start with \,
 because this can be generalized to proc expressions from arrow syntax
 simply by replacing the \ with proc.

 Take, for example, the following function definition:

 f (Left x) = g x
 f (Right y) = h y

 Now, let’s make an arrow version of it:

 f = proc e > case e of
 Left x > g < x
 Right y > h < y

 It would be great if we could write something like this instead:

 f = proc of
 Left x > g < x
 Right y > h < y
I don't think I was aware of the proc part.
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.
Simon
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