unsafeLocalState = unsafeDupablePerformIO?
marlowsd at gmail.com
Fri Jul 8 10:17:47 CEST 2011
We currently have
Foreign.Marshal.Unsafe.unsafeLocalState :: IO a -> a
unsafeLocalState = unsafePerformIO
however, unsafePerformIO in GHC is rather expensive, because it tries to
avoid the IO being executed more than once when there are multiple
processors. However, for the cases that we claim unsafeLocalState is to
be used for, it would be safe to use the cheaper unsafeDupablePerformIO
The only way to get at unsafeDupablePerformIO currently is from GHC.IO,
this would give users a legitimate way to get at a cheaper unsafePerformIO.
Or perhaps we should just export unsafeDupablePerformIO from
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