[Haskell-cafe] ACIO versus Execution Contexts

[Keean Schupke]

Adrian Hey wrote:

>If userInit is exported, it could reasonably be described as "global",
>but this doesn't matter because as far as users are concerned it's just
>a perfectly ordinary side-effectful, state manipulating IO function that
>works it's magic by unknown means. There's no reason for them to know
>or care that the some of the state it manipulates is top-level Haskell
>state rather than "real world" state,
>
I suppose you are right... After all I can always produce a replacement
for the MVar library that includes the indirection I want...

> and there's no possibility of
>anybody getting at the underlying MVar and accidently corrupting it.
>The only way it can be got at is by executing userInit.
>  
>
Keean.