I had the pleasure of studying with Paul Hudak, the creator of Haskell, and I remain highly intrigued by the language. I like your introduction a lot. A couple of things I would add in the relevance-to-Perl department:

Also, I know you're trying to keep it reasonably short, but I think it would be really cool to show an example of constructing recursive polymorphic types, and the fact that you can have different data constructors with completely different type arguments. In other words, the fact that in Haskell you can implement large parts of your program logic just by the way you design your types.

I like the lazy factorial example. My favorite lazy expressions in Haskell were the fibonacci sequence:

fib :: [Integer] fib = 1 : 1 : zipWith (+) fib (tail fib)

and the function for inserting commas in a string of digits according to standard notation:

inschar n c = foldr1 (\s1 s2 -> s1 ++ c : s2) . map (take n) . takeWhile (not . null) . iterate (drop n) commaize :: String -> String commaize = reverse . inschar 3 ',' . reverse

In reply to Re: RFC: A Perlesque Introduction to Haskell, Part One (DRAFT) by Errto
in thread RFC: A Perlesque Introduction to Haskell, Part One (DRAFT) by FoxtrotUniform

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