Re: [sigc] Re: [Boost-users] Signals & Slots

From: Doug Gregor (dgregor_at_[hidden])
Date: 2004-11-21 23:28:09

On Nov 21, 2004, at 8:09 PM, Carl Nygard wrote:

> On Sun, 2004-11-21 at 14:26, Murray Cumming wrote:
>> On Sat, 2004-11-20 at 15:58 -0500, Carl Nygard wrote:
>>>> 2. libsigc++2 uses sigc::signal<>, not sigc::signal[1/2/3/4/5]<>.
>>>
>>> Yup, and Boost.Signal has signal<void (float, string)> notation as
>>> well.  I was trying to keep the examples as identical as possible to
>>> show commonalities, but I'll make a note.
>>
>> The API here seems to be different, so it would be useful to show 
>> that.
>>
>> I don't think anybody is interested in using some secondary API
>> (probably semi-internal API) just because that API is similar in both
>> libsigc++ and Boost.Signal.
>
> Sorry, I thought the reason for the comparisons was as a first step for
> C++ standard library, so I figured the analysis should concentrate on
> underlying implementation instead of syntactic conveniences... although
> those conveniences go a long way toward making the library usable.  
> I'll
> update the docs...
>
> Regards,
> Carl

We should compare the "best" interfaces of both libraries, because we 
want to have the best interface to present to the C++ committee. For 
Boost.Signals, that's the "boost::signal<void(float x, string s)>" 
interface.

As for the interface vs. implementation question... the C++ committee 
is interested in interfaces and their semantic descriptions, only. 
Having an implementation is important to validate the interface (having 
two implementations is, of course, much better!), but implementation 
details need not be discussed. They do come into play when we talk 
about the best semantics we can get... for instance, whether 
disconnecting a slot is O(1) or O(lg n), etc.

        Doug