On Thu, Sep 06, 2012 at 09:24:13PM +0400, Stayvoid wrote:
Hello,
Could you explain this behaviour?
splitAt (-1) "Foobar" ("","Foobar") splitAt (-100) "Foobar" ("","Foobar")
That is simply how splitAt is defined. It treats negative values as if they were 0. If you are looking for an explanation of *why* this behavior was chosen, it is probably because Haskell lists are really *singly-linked lists*, not arrays. Taking something off the end of a list takes O(n) time and requires making a copy of the entire list. So it wouldn't be a good idea to encourage it. If you really need this sort of functionality often then perhaps you should be using a different type, such as Data.Text, which has functions for doing things efficiently at the end of some text: http://hackage.haskell.org/package/text -Brent