Haskell Platform proposal: Add the vector package

Simon Marlow marlowsd at gmail.com
Tue Jul 17 11:16:59 CEST 2012

On 16/07/2012 16:17, Roman Leshchinskiy wrote:
> Simon Marlow wrote:
>> Ah ok, so your concern was that you couldn't easily find out whether
>> runST was safe or not?  If you look at the library docs:
> Whether runST is safe or not has a huge impact on what ST code I can
> declare Trustworthy even if I don't use runST at all. IMO, the fact that
> ST code that doesn't do bounds checking must not be declared Trustworthy
> should be stated somewhere prominent especially since this does *not*
> apply to similar monads like IO and (presumably) STM. The library docs are
> not really a good place for this - who would ever look at the
> documentation of ST when figuring out Safe Haskell?

Ok, we can put something in the docs about ST.

The fact that you can't do arbitrary side effects in ST follows from the 
definition of safety and the fact that runST injects ST computations 
into pure computations.  So there's really no design choice here.  The 
same applies to the Par monad, and any monad that injects into pure 


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