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Re: Why vectors? Per Bothner 11 Aug 2008 07:29 UTC

Derick Eddington wrote:
> Why are vectors and not lists used for make-rtd's and rtd-constructor's
> fieldspecs arguments and for rtd-field-names's and rtd-all-field-names's
> return values?  Is the only reason to follow R6RS's use of vectors?  If
> so, I request lists be used instead because they're easier to deal with,
> as shown by how much list<->vector conversion is done in the ERR5RS
> reference implementation itself.  Using lists instead would increase the
> appeal of this SRFI to me, and I think to others also.  IMO,
> interoperating with the R6RS records procedures that deal in vectors
> without having to convert list<->vector is not a good enough reason
> compared to the benefit of using lists with one's primary record system
> of use, because interoperating at the procedural level where these
> vectors matter will be rare (I imagine).  Or is there a good reason to
> use vectors?

Well, of course performance-wise vectors are much more efficient than
lists as a general rule, but it mostly matters for either freequently-
accessed or long-term-retention sequences.  Clearly, the internal data
structures used to represent classes should be vectors.  In that case,
it can be more efficient to have reflective operations also return
(immutable) vectors - at least if return sequences can be the same
as the internal sequences.
--
	--Per Bothner
xxxxxx@bothner.com   http://per.bothner.com/