I don't even understand what you are trying to do :)
if you want to pattern match on the empty list
foo :: [a] -> [a]
foo [] = 0
foo (x:xs) = undefined
if you want to use the guard syntax
foo xs | null xs = 0
| otherwise = undefined
Ben
On 12 July 2011 10:02, Roelof Wobben
hello
Everyone thanks for the help.
I'm now trying to make this work on a empty list.
But my question is.
When the definition is :
[a] -> [a] [a]
Is it correct that I don't can use.
length xs = 0 | []
Roelof
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Subject: Re: [Haskell-beginners] function defenition. Do I understand it right? From: d@vidplace.com Date: Mon, 11 Jul 2011 18:56:42 -0400 CC: beginners@haskell.org To: rwobben@hotmail.com
On Jul 11, 2011, at 5:13 PM, Roelof Wobben wrote:
What I try to achieve is this:
[1,2,3,4] will be [1,2] [3,4]
[1,2,3,4,5] will be [1,2,3] [3,4,5]
So, I think what you want is this http://codepad.org/kjpbtLfR
Is that correct?
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