Re: When does ADJUST-ARRAY cons?
- From: Alain Picard <Alain.Picard@xxxxxxxxxxxxx>
- Date: Tue, 19 Jul 2005 17:34:58 +1000
Kent M Pitman <pitman@xxxxxxxxxxx> writes:
> Personally, I've never seen this use of displaced arrays. That doesn't
> make it a bad use, but points to the fact that people conceptualize
> the use of operators in different ways.
But you don't see anything fundamentally flawed with the
usage I'm proposing? That's kind of what I'd like to know,
as I've never had to use ADJUST-ARRAY before, and I was just
looking for some sort of speed hack. So if an implementation
is free to make the particular usage I have in mind very cheap,
I could contact my vendor and ask them to extend the implementation
in this manner.
Alternately, I could really do with some sort of function
like READ-LINE-INTO-STRING, which would be the analogue of
READ-SEQUENCE, which would take a string with a fill-pointer
as argument, and read characters into the string, adjust the
fill pointer (and presumably signal some sort of error if
the newline, or whatever designated terminating character,
was not found soon enough). If this could result into
some speed improvement (because it could be made not to cons)
I'd be very happy.
Maybe this sort of problem is not as ubiquitous as I thought.
It would be difficult to construe Larry Wall, in article
this as a feature. <1995May29.062427.3640@xxxxxxxxxxx>