On Tue, Apr 14, 2009 at 10:54 AM, rodrigo.bonifacio <rodrigo.bonifa...@uol.com.br> wrote: > Dear Sirs, > > I guess this is a very simple question. How can I convert IO [XmlTree] to > just a list of XmlTree? > > Regards, > > Rodrigo.
One good link on this topic is http://haskell.org/haskellwiki/Avoiding_IO Maybe there's no need for it be be IO [XmlTree], if you can write functions that instead produce/consume just [XmlTree]. They can always be turned later with liftM and whatnot into a IO [XmlTree] (but not the reverse). Doing as much as possible in pure code, and wrapping around it/calling it from a few short IO functions is the Haskell Way. Sometimes it looks hard to see, but XMonad is probably the best example here of how it can both be done where it looks infeasible ('What's a window manager but a bunch of IO?") and is rewarding (testability, etc. as exemplified by http://cgi.cse.unsw.edu.au/~dons/blog/2007/05/17) The best writeup on this seems to be http://www.cse.unsw.edu.au/~dons/talks/xmonad-hw07.pdf -- gwern _______________________________________________ Haskell-Cafe mailing list Haskell-Cafe@haskell.org http://www.haskell.org/mailman/listinfo/haskell-cafe
