[plt-scheme] let vs parameterize?

From: Jakub Piotr Cłapa (jpc at pld-linux.org)
Date: Mon Apr 16 18:57:36 EDT 2007

Robby Findler wrote:
> Another difference between parameters and fluid-let: in a fluid-let
> the values are not thread local, but in a parameter they are.

That's the main reason I was asking about this. R5RS doesn't mention 
threads but from the intuitive point of view making fluid-let 
thread-local seems to be a natural extension (it not, than fluid-let 
becomes pretty much useless in multi threaded programs). On the other 
hand it certainly would mix the semantics. Thanks for the clarification.

btw. I have another question:
fluid-let only affects code that uses the same binding of the variable. 
So if I declare two modules with a private variable of same name in both 
than fluid-letting one will only affect the code from the same module 
(so fluid-let respects the scoping of the original binding). Parameters 
also respect these rules, don't they?

Jakub Piotr Cłapa

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