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

Donn Cave donn at
Fri Jul 6 00:47:35 CEST 2012

The `multi-clause lambda' seems more elegant, if the syntactical
problems could be worked out.  I mean, unnamed functions are thus
just like named functions, something that you'd probably think to
try just as soon as you needed the feature.

I don't understand the issues well enough with the layout rules to
comment on Tyson Whitehead's ideas about that, and for the same
reason this may be a useless idea, but what if each clause were
introduced by \, would that clarify the column structure, or does
indented block structure require a less-indented `layout herald'?

  f = \ (Just a) (Just b) | a < 0 || b < 0 -> Nothing
      \ (Just a) (Just b) -> Just (a * b)
      \ _ _ -> Nothing


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