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Re: time to finalize srfi-17?

This page is part of the web mail archives of SRFI 17 from before July 7th, 2015. The new archives for SRFI 17 contain all messages, not just those from before July 7th, 2015.



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.