Hello David
Apropos the (unfortunately) frosty exchanges that greeted the first
release of UHC a couple of months ago, which argued that UHC wasn't
Haskell because it didn't implement n+k patterns, one could argue (at
least for rhetorical effect) that Haskell plus unsafePerformIO isn't
Haskell, I don't think you'll be able to find unsafePerformIO in the
report...
Best wishes
Stephen
2009/12/10 David Leimbach
That's not a "safe" way to think of 3rd party libraries. It is a convenient claim for promoting the language, and is probably more often than not the case though it does not quite capture the whole truth. unsafePerformIO can exist in any library you import,
[snip]
In short unsafePerformIO, while it's "supposed to be" avoided, may not be avoided as much as the advice given to do so :-).