[Haskell-cafe] Re: [Haskell] Top Level <-

[Ashley Yakeley]

Ashley Yakeley wrote:
>> I don't really follow this. Do you mean the minimal such scope, or the 
>> maximal such scope? The problem here is not about separate calls to 
>> newIORef, it's about how many times an individual <- will be executed.
> 
> Two IO executions are in the same "global scope" if their resulting 
> values can be used in the same expression. Top-level <- declarations 
> must execute at most once in this scope.

Better:

Two newIORef executions are in the same "global scope" if their 
resulting refs can be used in the same expression. Top-level <- 
declarations must execute at most once in this scope.

-- 
Ashley Yakeley