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Subject: Re: [boost] Name of namespace detail
From: Mateusz Loskot (mateusz_at_[hidden])
Date: 2009-10-13 11:25:26

Stewart, Robert wrote:
> Mateusz Loskot wrote:
>> Recently, I've participated in a very interesting discussion, on
>> ACCU members mailing list, about prefixes and suffixes like Base or
>> _base nad Impl or _impl, as misused, irrelevant and confusing,
>> meaningless, etc. For example, how to properly name elements of
>> PIMPL idiom and similar.
> As has been noted, if a class is a private, implementation detail,
> then some naming convention for that purpose is useful. I've seen
> "IC" used as a prefix to mean "implementation class." I've seen
> "Impl" or "_impl" as a suffix for the same purpose. These names
> indicate that they are not for library client use, even if they
> happen to be visible.

Yes, I've seen exactly the same use if these.
It looks _impl, _base, all these are conventions well settled
in the C++ world. I don't mind using them myself.

>> During the discussion I suggested that 'detail' is a good name for
>> namespace dedicated to implementation details being not a part of
>> public interface of a component. I got answer that it as the same
>> issues (it's meaningless) as Impl etc.
> While I've never been comfortable with "detail" and greatly prefer
> "details," the point is that it is a namespace, nested within
> another, more meaningfully named namespace, that holds implementation
> details that should be ignored by those using the enclosing
> namespace. There's no need for a name with any more meaning than
> that in many cases.

Understood. I've been following the same and I'm comfortable with it,
however during recent discussions made me asking myself if and where
thing could be improved.

> However, it is quite reasonable to nest other namespaces within
> detail(s) in order to segregate details, all related to the outer
> namespace, by purpose. That is, if there are too many unrelated
> implementation details in the foo::details namespace, then
> foo::details should be subdivided.

Yes, makes sense to me.

>> It raised some questions for myself, being interested in improving
>> my craft, I would like to learn better about the name of namespace
>> detail. I use detail name myself. Any better names for bucket with
>> implementation details?
> Any time there is value in grouping things by a categorical name, do
> so. However, when those are implementation details of something else
> that should be visible to clients, then those details should be in a
> namespace like "details" to set them apart.

Very well said. I'll take it as a rule and definition of how to use
namespace details.

Best regards,

Mateusz Loskot,

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