On Wed, 20 Aug 2014 14:31:42 -0700, Per Bothner <p...@bothner.com> said:
> ...
> Many programs needs to "build" a
> sequence, typically appending at the end
> each element as it is produced. Using an
> array that gets reallocated (doubled)
> when full is usually the most efficient
> representation. Having a standard
> re-sizable (growable) vector type would
> simplify the programming.
> I added string-append! to Kawa. It seems
> to be a good idea to also add
> vector-append!.
As a corroborating side note (for what
it's worth), the designers of Common Lisp
found it fit to include VECTOR-PUSH and
VECTOR-PUSH-EXTEND, which also covers
strings. Unlike NCONC for lists,
however, Common Lisp does not offer a
primitive to append a whole (sub)vector
destructively. This can be done with a
call to REPLACE [*].
Then Common Lisp has nothing like
`vector-insert'. For the non-destructive
variant, one can compose CONCATENATE and
SUBSEQ. The destructive variant can be
done with two calls to REPLACE [*].
_________
[*] possibly after calling ADJUST-ARRAY,
and incrementing a fill pointer as
needed
---Vassil.
--
Vassil Nikolov | Васил Николов | <vniko...@pobox.com>
"Be careful how you fix what you don't understand." (Brooks 2010, 185)
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