[Haskell-beginners] Prelude Implementation of Last overlapping patterns?

[Benjamin Edwards]

Because patterns are matched in order and the first one match is taken.
On 24 Dec 2011 17:49, "Mark Stoehr" <stoehr at cs.uchicago.edu> wrote:

> The standard Prelude implementation of 'last' is as follows
> \begin{code}
> last             :: [a] -> a
> last [x]         =  x
> last (_:xs)      =  last xs
> last []          =  error "Prelude.last: empty list"
> \end{code}
>
> Isn't [x] equivalent to (x:[]) hence wouldn't [1] match both [x] and
> (_:xs)?  If that's the case then we would have
> last [1] == 1
> and
> last [1] == last []
>
> but that doesn't happen. Why?
>
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