Idempontent IO actions and unsafeSTMToIO

Robert van Herk rherk at
Sat Aug 6 14:12:06 EDT 2005

Hi all,

Is it true to say that to perform idempotent IO actions inside a STM 
monad by using unsafeSTMToIO is safe? I mean something like:

do ... -- some STM actions
     unsafeSTMToIO a -- Here, a is an idempotent IO action
     ... -- some other STM actions

What I read from the various sources on the web is that unsafeSTMToIO is 
just unsafe in the sence that the IO actions may be performed multiple 
times. So I recon that, if the IO actions are idempotent, there would be 
no problem.

Am I correct?


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