5 Feb
2007
5 Feb
'07
5:21 p.m.
On 2/4/07, Eric Olander
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.