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Re: Why vectors?

This page is part of the web mail archives of SRFI 99 from before July 7th, 2015. The new archives for SRFI 99 contain all messages, not just those from before July 7th, 2015.

[Off-topic, but a pet peeve of mine.]

Elf wrote:
As records are essentially vectors (constant sized, fixed order, etc) with
procedures mapping to indices, using lists would be a significant performance
cost for no benefit: one generally doesn't iterate over the elements of a

Regardless, it is much faster on modern processors to iterate over the
elements of a vector than the elements of list.  Never (well,
almost never) use linked lists if you care about performance.  Even
if you need to build a sequence incrementally it's usually faster to
use a vector and double its size when needed.

Remember that on a modern desktop-or-above processor computation is
free to a first approximation - what is expensive are cache misses!

That is why 40-year-old APL (with its potential for parallelism) is the
language of the future ...
	--Per Bothner
per@xxxxxxxxxxx   http://per.bothner.com/