[Haskell-cafe] [ANN] acme-dont-1.2 - a "don't" construct

Joachim Breitner mail at joachim-breitner.de
Thu Apr 2 09:03:42 UTC 2020


Hi,

Am Mittwoch, den 01.04.2020, 14:33 +0100 schrieb Richard Eisenberg:
> Perhaps with https://github.com/ghc-proposals/ghc-proposals/pull/216,
> we can have `Not.do` introduce an indentation-aware block of
> comments. This would surely show off the power, elegance, and beauty
> of Haskell.

Unfortunately, not:

  Not.do print "Hello"

will still desguar to 

  print "Hello"

which points to a crucial design flaw of do notation (and which could
be fixed as part of #216): The inability to specify an operation to
apply to the do-block as a whole.


Cheers,
Joachim
-- 
Joachim Breitner
  mail at joachim-breitner.de
  http://www.joachim-breitner.de/




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