Documentation of atomicModifyMutVar# does not show properly
The actual documentation in the source is:
-- | Modify the contents of a @MutVar\#@. Note that this isn\'t strictly -- speaking the correct type for this function, it should really be -- @MutVar# s a -> (a -> (a,b)) -> State# s -> (# State# s, b #)@, however -- we don\'t know about pairs here.
It actually shows as this in the docs, note the incomplete signature:
Modify the contents of a MutVar#. Note that this isn't strictly speaking the correct type for this function, it should really be MutVar s -> ( s, b #), however we don't know about pairs here.