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

John Meacham john at repetae.net
Mon Sep 1 18:03:29 EDT 2008

On Mon, Sep 01, 2008 at 10:45:05PM +0100, Ganesh Sittampalam wrote:
>> Actually all this use of the tainted and derogatory term "global
>> variable" is causing me to be imprecise. All MVars/IORefs have "global" 
>> main/process scope whether or not they're bound to something at the
>> top level.
> "Global variable" is exactly the right term to use, if we are following  
> the terminology of other languages. We don't call the result of 
> malloc/new etc a "global variable", unless it is assigned to something 
> with top-level scope.

global variable is not a very precise term in other languages for
various platforms too a lot of times.  for instance, windows dll's have
the ability to share individual variables across all loadings of said
dll. (for better or worse.) Haskell certainly has more advanced scoping
capabilities than other languages so we need a more refined terminology.
I think 'IO scope' is the more precise term, as it implys the scope is
that of the IO monad state. which may or may not correspond to some
external 'process scope'.


John Meacham - ⑆repetae.net⑆john⑈

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