[Haskell-cafe] More death to partial functions: Should -fwarn-incomplete-uni-patterns be enabled with -Wall?

[Joachim Breitner]

Hi,

Am Sonntag, den 08.11.2015, 09:30 +0000 schrieb Tom Ellis:
> Simon's code is inadvisable, in my opinion.  It is
> 
>     f xs | null xs = blah
>          | otherwise = x+1
>          where
>            (x:_) = xs
> 
> where it really should be
> 
>     f xs = case xs of []    -> blah
>                       (x:_) -> x + 1
> 

yes, in this particular, small example

But often you have complex decisions in the guards that are not
obviously related to the pattern match, and the where-bound and
partially-pattern-matched value are used in multiple branches of the
guard.

Greetings,
Joachim

-- 
Joachim “nomeata” Breitner
  mail at joachim-breitner.de • http://www.joachim-breitner.de/
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