I really like the amount of nonsense.)<p>It begins with <i>head is a mistake! It should not be in the Prelude. Other partial Prelude functions you should almost never use include tail, init, last, and (!!). From this point on, using one of these functions on a homework assignment will lose style points!</i><p>And here is a proposal:<p><pre><code> data NonEmptyList a = NEL a [a]
nelToList :: NonEmptyList a -> [a]
nelToList (NEL x xs) = x:xs
listToNel :: [a] -> Maybe (NonEmptyList a)
listToNel [] = Nothing
listToNel (x:xs) = Just $ NEL x xs
headNEL :: NonEmptyList a -> a
headNEL (NEL a _) = a
tailNEL :: NonEmptyList a -> [a]
tailNEL (NEL _ as) = as
</code></pre>
Dear sirs, a List is a recursive data structure <i>by definition</i>. Non-recursive List is an unimaginable nonsense. What was made here with a name of safe(!) NonEmptyList is some ugly Pair with lots of syntactic noise.<p>How could you get the last element from your NonEmptyList? How could you tell how many elements in it?)<p>But, of course, never ever use these ugly unsafe lists - they might be empty! Use safe NonEmptyList because in Haskell everything is safe. And never try to think what the fuck you are reading.
The author and teacher of this course, Brent Yorgey, is one of those rare guys who is both a fantastic lecturer and a fantastic researcher.<p>For Penn's fuller version of this course, check out CIS 552[1]. Dr. Stephanie Weirich is also a fantastic lecturer, and a GHC contributor to boot (IIRC).<p>[1] <a href="http://www.seas.upenn.edu/~cis552/12fa/" rel="nofollow">http://www.seas.upenn.edu/~cis552/12fa/</a>
Wow, thanks for this, it's exactly what I needed.<p>I started from LYAH and the only thing missing from it were some exercises so I could retain the information that was presented in each chapter. Otherwise, it's a fantastic book.
I really wanted to learn functional programming when my university offered it, but unfortunately it's crunched in a horribly busy term and I'm not willing to risk core modules for it if I end up struggling.<p>That said, I really do want to learn it and find MOOCs a really useful tool, if anybody has any suggestions for any they've used (or the one linked, I'm unclear if that's for students at that university only) that'd be awesome!
I'm currently trying to learn functional programming through Haskell. Glad to have found another resource, plus this cheat sheet linked from the page looks handy: <a href="http://cheatsheet.codeslower.com/" rel="nofollow">http://cheatsheet.codeslower.com/</a>