Wow, uniplate is the library from my dreams :)
I knew there should be easy, elegant and simple solution (I hate brute
force, that's why I start using Haskell).
Many thanks.
2009/3/26 Neil Mitchell
Hi
f1 = foo 5 f2 = foo 8 f3 = foo 9
I want to extract a list [5, 8, 9] (suppouse function takes only one argument)
Firstly, use haskell-src-exts and Language.Haskell.Exts - its a much better library, deals with many extensions, and gives you everything Language.Haskell did.
parser works pretty good, but its output data type is terrible. As I understand, I need to extract all objects that looks like HsApp (HsVar (UnQual (HsIdent "foo"))) ....
It's trivial, if you use a generics solution, say Uniplate: http://community.haskell.org/~ndm/uniplate
[x | App foo x <- universeBi src, prettyPrint foo == "foo" ]
I often use prettyPrint to follow down Ident/Qual/UnQual paths without having to know as much of the data type. Using universeBi makes it easy to find everything that occurs everywhere.
If you attempt this without using a generics library, I'd say you are destined to fail.
Thanks
Neil
-- Best regards, Vasyl Pasternak