"Matthew Brecknell"
Pete Kazmier:
I understand the intent of this code, but I am having a hard time understanding the implementation, specifically the combination of 'fix', 'flip', and 'interate'. I looked up 'fix' and I'm unsure how one can call 'flip' on a function that takes one argument.
I threw that in there because I figured you were up for another challenge. :-)
Haskell has a way of making one feel dumb. This is by far the most challenging programming language I've ever used.
It took me ages to get some clue about how to use fix, quite apart from combining it with flip. The concept of passing the output of a function as one of its parameters ("tying the knot") can be difficult to accept, particularly if you haven't studied lambda calculus.
This is a bit mind boggling. Do you have any trivial examples that may help my understanding?
Note that I could have just written this:
let iterate a = do ... iterate a' ... iterate accum
In the meantime, I'm more than happy to claim ignorance and stick with the above version which is very accessible to us mere mortals.
So with my use of "flip fix", I'm really just calling fix on the anonymous function (\iterate accum -> ...), and then the parameter ("accum") is passed to the function returned by fix. So now you just need a couple of weeks (or months if you're as slow as me) to understand what fix is all about... :-)
I won't try to understand fix just yet, but I'm still confused by the type of fix: fix :: (a -> a) -> a It appears to me that it takes a function as an argument, and that function takes a single argument. So how are you passing fix an anonymous function taking 2 arguments? Sorry if I have beaten this horse to death, but my pea-sized brain is working overtime here. Thanks for all of the help. Pete