Things can go arbitrarily wrong if you misuse unsafePerformIO, you can even subvert the type system.<br><br><div><span class="gmail_quote">On 9/26/07, <b class="gmail_sendername">Jorge Marques Pelizzoni</b> <<a href="mailto:jpeliz@icmc.usp.br">
jpeliz@icmc.usp.br</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><br>Hi, all!<br><br>This is a newbie question: I sort of understand what unsafePerformIO does
<br>but I don't quite get its consequences. In short: how safe can one be in<br>face of it? I mean, conceptually, it allows any Haskell function to have<br>side effects just as in any imperative language, doesn't it? Doesn't it
<br>blow up referential transparency for good? Is there anything intrinsic to<br>it that still keeps Haskell "sound" no matter what unsafePerformIO users<br>do (unlikely) or else what are the guidelines we should follow when using
<br>it?<br><br>Thanks in advance. Cheers,<br><br>Jorge.<br><br>_______________________________________________<br>Haskell-Cafe mailing list<br><a href="mailto:Haskell-Cafe@haskell.org">Haskell-Cafe@haskell.org</a><br><a href="http://www.haskell.org/mailman/listinfo/haskell-cafe">
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