Thank you for your work! I just glanced over it but I'll suggest it to be linked to from the homepage of my university's functional programming course. However, thirteen pages can hardly be called "cheatsheet". It's more like a quick reference. You could add [100,99..] "infinite liste of numbers from 100 downwards" to you "numbers" section, as it is an example where the range does go backward. Adrian Am 11.10.2008 um 01:08 schrieb Justin Bailey:

All,

I've created a "cheat sheet" for Haskell. It's a PDF that tries to summarize Haskell 98's syntax, keywords and other language elements. It's currently available on hackage[1]. Once downloaded, unpack the archive and you'll see the PDF. A literate source file is also included.

If you install with "cabal install cheatsheet", run "cheatsheet" afterwards and the program will tell you where the PDF is located.

The audience for this document is beginning to intermediate Haskell programmers. I found it difficult to look up some of the less-used syntax and other language stumbling blocks as I learned Haskell over the last few years, so I hope this document can help others in the future.

This is a beta release (which is why I've limited the audience by using hackage) to get feedback before distributing the PDF to a wider audience. With that in mind, I welcome your comments or patches[2].

Justin

[1] http://hackage.haskell.org/cgi-bin/hackage-scripts/package/ CheatSheet [2] git://github.com/m4dc4p/cheatsheet.git _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe

On Saturday 11 October 2008 01:08:15 Justin Bailey wrote:

This is a beta release (which is why I've limited the audience by using hackage) to get feedback before distributing the PDF to a wider audience. With that in mind, I welcome your comments or patches[2].

Justin

[1] http://hackage.haskell.org/cgi-bin/hackage-scripts/package/CheatSheet [2] git://github.com/m4dc4p/cheatsheet.git

Looks good! Some minor issues: - sometimes it is a bit verbose for a cheatsheet; for example the reference to language C in the section about the layout rule. - in the section about strings, you give an example of a syntax error; it would be sufficient to show what is right. - in the section about operator precedence you define 'div1' to be right associative. Instead, you could show where right associativity is actually useful (>>=, ...). - The explanation of the layout rule is wrong. If you define more than one value in a let declaration, then it is only required that the identifiers start on the same column. - When I started to learn Haskell, I had problems with the use of (.) and ($). I had learned what function application and lambda abstractions look like, but then I looked at Haskell code written by experienced Haskellers and found expressions like (map (succ . succ) $ 1:xs) that I did not understand. A small section describing how to read such expressions could be useful for beginners. - the section about do-notation is more a mini-tutorial than a cheatsheet. Instead, you could show two or three examples that demonstrate how do- notation, list comprehensions and the operator >>= relate. That is what I had to look up more than once until I got used to it. There is also an example of what is wrong, where showing the right thing would have sufficed.

On Fri, 10 Oct 2008, Justin Bailey wrote:

I've created a "cheat sheet" for Haskell. It's a PDF that tries to summarize Haskell 98's syntax, keywords and other language elements. It's currently available on hackage[1]. Once downloaded, unpack the archive and you'll see the PDF. A literate source file is also included.

..

The audience for this document is beginning to intermediate Haskell programmers. I found it difficult to look up some of the less-used syntax and other language stumbling blocks as I learned Haskell over the last few years, so I hope this document can help others in the future.

..

Justin

[1] http://hackage.haskell.org/cgi-bin/hackage-scripts/package/CheatSheet [2] git://github.com/m4dc4p/cheatsheet.git _______________________________________________

Justin (and everyone now contributing to this), thanks. This type of thing is very helpful. There is a well-known one-page cheat-sheet like this for Perl5 (and a newer one for Perl6 too). You can see it by typing `perldoc perlcheat` on a system with Perl. I wonder if we don't need something like that. On a related note, I had come up with this short list to help with how to read the Haskell symbols. I email this out when trying to get new people started: ----- Haskell symbology One thing that I found very difficult at first was how to read a lot of the symbols in the Haskell code. I made up a small cheat-sheet that explains how to read some of it: Some definitions of Haskell symbols: :: "has type" -> "to" The type 'Integer -> Integer' takes Integer as an argument and evaluates to an Integer. We say this type is "Integer to Integer" => "evaluates" or "reduces to" Used in function type signatures, read something like this: foo :: (Bar b) => b -> c For all instances of type class Bar (here referred to as b), foo is a function from b to c. Or foo "has type" b to c. [a] "list of a" The family of types consisting of, for every type a, the type of lists of a. : "cons" List cons operator, adds first argument to the front of second, part of the List monad: (:) :: a -> [a] -> [a] Read: cons has type a to list of a to list of a !! List index operator [ 1, 2, 3 ] !! 1 = 2 (lists are 0-based) (!!) :: [a] -> Int -> a Read: (!!) has type list of a to Int to a | "such that" <- "drawn from"

...

= "bind" Part of class Monad

...

"then" Part of class Monad

-- Dino Morelli email: dino@ui3.info web: http://ui3.info/d/ irc: dino- pubkey: http://ui3.info/d/dino-4AA4F02D-pub.gpg

On Fri, Oct 10, 2008 at 7:08 PM, Justin Bailey wrote:

This is a beta release (which is why I've limited the audience by using hackage) to get feedback before distributing the PDF to a wider audience. With that in mind, I welcome your comments or patches[2].

On page 1, you list 'return' as a reserved word, but it isn't. It's just a function, and in fact you can redefine it.