Re: Slightly OT: Compilation question

James Kanze <>
Wed, 18 Jun 2008 00:33:01 -0700 (PDT)
On Jun 17, 1:04 pm, peter koch <> wrote:

On 17 Jun., 10:47, James Kanze <> wrote:> On Jun 17,=

 2:14 am, Paul Hsieh <> wrote:


I will not argue that there might be cases, where a custom
string- class or (more rarely) a custom std::vector could
improve performance, but in the dominating number of cases
this will not be so, and in the rest of these, the performance
hit will probably not really be something worth bothering
about, so you will almost always start with std::vector or
std::string and only change strategy when measurements show
that these elements are the culprit. The exception is when you
have relatively small, fixed-size vectors. Boost has code for

In this regard, if the abstraction in question is central to
your application, you should wrap the use of the standard
classes in your own class, which should provide exactly the
interface needed, and no more. In that way, if it should be
necessary to replace them, you can do so without having to
implement the full interface, and without modifying any of the
client code.

This is really, more than anything else, why C++ has less
performance problems than C. It supports better encapsulation,
and better encapsulation allows you to correct the performance
problems, once the profiler has shown where they were, without
doing a major rewrite.

James Kanze (GABI Software)
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