How to define an operator to show a sequence of polymorphic things

Derek Elkins ddarius86@hotmail.com
Tue, 22 Apr 2003 12:19:59 -0400







>From: Bernd Holzmüller <holzmueller@ics-ag.de>
>To: Haskell@haskell.org
>Subject: How to define an operator to show a sequence of polymorphic things
>Date: Tue, 22 Apr 2003 17:11:34 +0200
>
>Hi all,
>
>I'd like to have a better way for "showing" a list of things, e.g.
>
>show (f1 t) ++ show (f2 t) ++ show (f3 t) ++ ....
>
>I would love to just write: (f1 # f2 # f3) t but I do not see how to define 
>an operator like # in Haskell without applying show over again on the first 
>arguments (i.e. f1 and f2). Because polymorphic lists are not possible, I 
>can not define # as to write [f1,f2,f3] # t either.
>
>Any idea?
>
>Regards, Bernd
>
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x # r = show x ++ r
end = ""

1 # True # 'a' # end ==> "1True'a'"


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