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From: Robert A Duff <bobduff@shell01.TheWorld.com>
Newsgroups: comp.lang.ada
Subject: Re: Reserve_Capacity for Unbounded_String?
Date: Tue, 24 Jul 2007 19:41:55 -0400
Organization: The World Public Access UNIX, Brookline, MA
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Date: 2007-07-24T19:41:55-04:00
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"Randy Brukardt" <randy@rrsoftware.com> writes:

> "Adam Beneschan" <adam@irvine.com> wrote in message
> news:1185203238.701948.307410@m37g2000prh.googlegroups.com...
> ...
>> > Is this a reasonable approach if performance is of concern?
>>
>> I sure wouldn't count on this.
>
> I second (or is that "third") Adam and Jeff's comments.

I said the opposite, but I guess I'm convinced by your (and Adam and
Jeff's) arguments that one should not depend on this particular
"efficiency hack".  But...

> For Janus/Ada, Unbounded_String is just a controlled wrapper around "access
> String"; in particular, the length is the length of the item
> allocated.

Are you saying that:

    for I in 1..N loop
        Append (Some_Unbounded_String, 'x');

causes a free and a "new" and a copy every time around the loop?

- Bob