(Pattern) Guards in lambdas

Claus Reinke claus.reinke at talk21.com
Wed Oct 18 06:44:29 EDT 2006

>> suggestion: undo removal of guards from lambdas, especially
>> (but not only) if pattern guards make it into the language.
> See the existing proposals
>    http://hackage.haskell.org/trac/haskell-prime/wiki/LambdaCase
>    http://hackage.haskell.org/trac/haskell-prime/wiki/MultiWayIf

thanks. I'm a fan of the correspondence principle, and as we have
a LetCase, there should be a LambdaCase as well (the other seems
to be inspired by Lisp's cond?). but the syntax is slightly awkward.
is there a reason not to merge LambdaCase and Lambda, thus 
addressing both my suggestion and the LambdaCase proposal?

    f <pat> | <patguard> = <rhs>

    \ <pat> | <patguard> -> <rhs>

    case x of <arms>

    (\ <arms> ) x


ps. strawpoll-2 has both LambdaCase and MultiWayIf as 'no'.
    but that is numbers, not rationale..

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