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Re: Fundamental design flaws

This page is part of the web mail archives of SRFI 44 from before July 7th, 2015. The new archives for SRFI 44 contain all messages, not just those from before July 7th, 2015.

On Thu, Oct 30, 2003 at 09:05:04AM -0800, Tom Lord wrote:
> Perhaps in all cases, the optional equivalence predicate to a
> constructor is mostly just a hint.
> If I make a hash table using EQV? but then modify it with:
> 	(dictionary-set! d k v)		; set using equal?
> instead of
> 	(dictionary-setv! d k v)	; set using eqv?

> then perhaps the results are simply undefined.   The non-generic
> interface to (normal) association lists works that way, for example.  
> I've certainly used hash-table libraries that work that way.

But why build in so much semantic uncertainty when the utility of 
changing equivalence in flight is limited to what I imagine are some 
pretty unusual cases?


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