On 2/4/07, Eric Olander <[EMAIL PROTECTED]> wrote:
Hi,
I'm still somewhat new to Haskell, so I'm wondering if there are better
ways I could implement the following functions, especially shiftl:
>> moves the last element to the head of the list
shiftl :: [a] -> [a]
shiftl [] = []
shiftl x = [last x] ++ init x
Well, you could try this, though I'm actually sure it's any faster:
shiftl (x1:x2:xs) = last:x1:init
where last:init = shiftl (x2:xs)
shiftl [x] = [x]
shiftl [] = error "shiftl: empty list"
Or, if you don't want to give an error on [], omit the last line and
replace both of the [x] with xs.
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