On Sat, 2007-08-18 at 20:35 +0200, Peter Verswyvelen wrote:
When reading an article about tail recursion (http://themechanicalbride.blogspot.com/2007/04/haskell-for-c-3-programmers. html) I came across the follow statements:
"If you can write a non-recursive function that uses the colon syntax it is probably better than a tail recursive one that doesn't. This is because Haskell's lazy evaluation enabled you to use the non-tail recursive version on an infinite stream without getting a stack overflow. "
and
""Unfortunately", laziness "gets in the way". While transforming non-tail-recursive code to a tail-recursive form is important and useful for functional programming in general, dealing with laziness requires a little more care, and often "non-tail-recursive" versions are preferrable. flatten is an example of this, the first version is better in many ways. While I don't believe it happens in this case, oftentimes naively writing code "tail-recursively" in Haskell will actually -make- it overflow the stack. Another (actual) benefit of the first version of flatten is that it will work on infinite lists. http://www.haskell.org/hawiki/StackOverflow gives a simple example and some explanation."
That page was migrated here: http://www.haskell.org/haskellwiki/Stack_overflow