Re: [cpp-netlib-devel] URI processing (Was Re: Work Left)

[Dean M. B. <mik...@gm...>]

Hi Glyn,

On Mon, Oct 13, 2008 at 5:47 PM, Glyn Matthews <gly...@gm...> wrote:
>
> 2008/10/13 Kim Gräsman <kim...@gm...>
>>
>> On Mon, Oct 13, 2008 at 04:04, Dean Michael Berris
>> > That raises a good issue though: should we have a single place to have
>> > the tags hierarchy depicted?
>> >
[snip code]
>>
>> It feels a little strange pushing the tags together, but I can't say
>> why, really... It creates sort of a hotspot, where everybody will have
>> to make edits in order to add new protocols, etc. That's probably not
>> a huge problem.
>
> It could be a problem.  I share your concern about this.  But I don't know a
> solution to this yet.
>

Yeah, I thought about it a little more, and instead of using a 'struct
tags' I think it should remain a namespace. So it'd look like:

namespace network { namespace tags {
  struct default_ { };
} }

That way we can add more tags to this central namespace as protocols
get implemented along the way.

>>
>> > That way we can build traits on top of this hierarchy under a
>> > different namespace 'traits':
>> >
>> > namespace network { namespace traits {
>> >  template <class Tag> string;
>> >  template <class Tag> buffer;
>> >  template <class Tag> ostringstream;
>> >  template <class Tag> char_;
>> >  // ...
>> > } }
>>
>> I think it makes sense to keep the traits together, there's bound to
>> be a lot of overlap (especially around strings).
>
> right.  But I think it might be better named:
> namespace network { namespace traits {
> template <class Tag> string_type;
> template <class Tag> buffer_type;
> template <class Tag> ostringstream_type;
> template <class Tag> char_type;
> }}
>

The _type will then be redundant for using traits:

template <> struct string_type<network::tags::default_> {
  typedef std::string type;
};

//...

string_type<>::type instance; // ugly? redundant _type and ::type?

> On an unrelated note, doesn't using ostringstream always require
> basic_string?  And char_type is not orthogonal to string_type and char_type.
>

template <> string<network::tags::default_> {
  typedef std::string type;
};

template <> struct string<network::tags::wide_default_> {
  typedef std::wstring type;
};

template <> struct ostringstream<network::tags::default_> {
  typedef std::ostringstream type;
};

template <> struct ostringstream<network::tags::default_> {
  typedef std::wstringstream type;
};

:-D

-- 
Dean Michael C. Berris
Software Engineer, Friendster, Inc.