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I'm not sure if "iterate" counts as loop forever?

I don't think there can be a "loop forever" construct in haskell?

why not?

in OCaml, it is simply: let loop(f) = f() ; loop(f) and is only useful together with exceptions and side-effects.

and in Haskell, it is simply: loop f = f >> loop f or, as there is little difference between control structures and other data structures, you can convert the latter into the former, using the list version of loop, called repeat: loop f = mapM_ id $ repeat f or simply: loop = foldr1 (>>) . repeat example (get ready to hit that interrupt key;-): loop (putStrLn "hi")

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I can't remember any %-based sprintf off the top of my head, but hey, who'd want one anyway?

me! I've always wondered how you internationalize a program without it?

eg: "This encryption key is too simple (must be at least %d characters long)" "The package %s needs to be installed. Do you want to install it?"

(I agree you don't need the full power of sprintf for this)

indeed not. you only want to factor out the strings, so that they can be collected in a single space for the translators/customizers convenience. functional abstraction allows you to just do that (then put the functions into a module per language, or collect them in tuples/records, and link or select as appropriate): encryptionTooSimple d = "This encryption key is too simple (must be at least " ++(show (d::Integer))++ characters long)" packageMissing s = "The package "++s++" needs to be installed. Do you want to install it?" but if you absolutely want printf-style formatting, Danvy's solution is very nice and simple (once someone had the idea;-): int k r x = k (r++(show (x::Integer))) -- an Integer str k r x = k (r++x) -- a String s x k r = k (r++x) -- format String fragment nl = s "\n" -- newline format p = p id "" (similar continuation-based functions for other types) Now you can try it in Hugs: Main> :t format $ s "age: " . int . s " name: " . str . nl format $ s "age: " . int . s " name: " . str . nl :: Integer -> [Char] -> [Char] Main> format ( s "age: " . int . s " name: " . str . nl ) 10 "IGS" "age: 10 name: IGS\n" See: RS-98-12 Olivier Danvy. Functional Unparsing. May 1998. 7 pp. This report supersedes the earlier report BRICS RS-98-5. Extended version of an article to appear in Journal of Functional Programming. http://www.brics.dk/RS/98/Ref/BRICS-RS-98-Ref/BRICS-RS-98-Ref.html#BRICS-RS-...

i don't put any non-simple functions, the main aim is not to show how it can be done, but what are the various names used in various languages.

but it is one of the major features of functional languages that it is so easy to compose/reuse functionality! this is why Haskell doesn't need a name for everything - composing the functions can be as simple as (and more flexible than) composing the names. Claus