Recently, I've been doing automatic testing with Haskell and QuickCheck. Some time I have got some fails, but the program retrieved [(),()] as checked argument.
What does "[(),()]" mean?
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fant0me
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1A list of two *units*. – Eugene Sh. Aug 29 '16 at 16:38
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1Meaning depends on the observer. – Daniel Wagner Aug 29 '16 at 17:06
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That's a list of two () (or "unit") values.
Prelude> :t [(),()]
[(),()] :: [()]
Prelude> :info ()
data () = () -- Defined in ‘GHC.Tuple’
A list is not an array; an array is flat, with constant-time indexing. A list is a nested recursive type.
jberryman
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