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Re: time to finalize srfi-17?



Per Bothner <per@xxxxxxxxxxx> writes:
> Shriram Krishnamurthi <shriram@xxxxxxxxxxx> writes:
> > Matthias and others have repeatedly raised
> > objections to it, on the grounds that it conflates two distinct
> > notions, and these haven't ever been properly answered.
> 
> I have argued in a number of
> responses that the notions are highly related, and that it is
> plausible to view variables as settable components of an
> environment.  

And your arguments are at best partial approximations to the actual
semantics of set!. The more that I ponder the issue, the more
clear the *difference* between set! and structure update becomes. set!
makes changes in the bindings of its continuation, structure-update
makes global changes in a data structure. set! is more like a function
call, structure updates are simple assignments.

> However, I would rather withdraw my proposal than change this part
> of it.)

Please do. Either.

> There seem to be two main classes of objections:

But you seem to be missing objection class 3: set! is not an
assignment operator (although it can be implemented as one).

david rush
-- 
And I have no problems with SRFIs that I think are stupid. I'm just
not going to be silent about them.