[saga-rg] C++ binding: question

[Thilo Kielmann]

The double constructor seem OK to me.

Thilo

On Fri, Nov 04, 2005 at 02:12:38PM -0600, Andre Merzky wrote:
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> Date: Fri, 4 Nov 2005 14:12:38 -0600
> From: Andre Merzky <andre at merzky.net>
> To: Simple API for Grid Applications WG <saga-rg at ggf.org>
> Subject: [saga-rg] C++ binding: question
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> Hi all, 
> 
> here is another question about the C++ language binding we
> stukmbled upon.  The API spec says that the session is an
> optional argument to each object creation in SAGA.  If the
> session is not given, a default session (theSession) is to
> be associated with the object.
> 
> Now, consider a object which has a number of optyional
> parameters already (example not spec conform):
> 
>   saga::file (string url, mode=saga::file::mode::RO, saga::session s);
> 
> If a programmer wants to specify a session, he NEEDS to
> specify mode, and all other optional parameters of the
> constructor.  For a programmer who always specifies a
> session that is awkward.
> 
> OTOH, a constructor like
> 
>   saga::file (saga::session s, string url, mode=saga::file::mode::RO);
>   
> would giove that programmer the ability to use session and
> rely on parameters defaults, but for another programmer who
> does not use an explicit session it would require to ALWAYS
> specify the session anyway:
> 
>   saga::file f (theSession, url);
> 
> 
> The solution we would like to propose is to introduce two
> versions of all constructors:
> 
>   saga::file (                 string url, mode=saga::file::mode::RO);
>   saga::file (saga::session s, string url, mode=saga::file::mode::RO);
> 
> which would accomodate both use cases nicely.  To be sure:
> that affects only the C++ language bindings - that might
> look totally different for other languages.
> 
> Any comments?  If not, we go for the proposed solution...
> 
> Cheers, Andre.
> 
> 
> -- 
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> | Andre Merzky                      | phon: +31 - 20 - 598 - 7759 |
> | Vrije Universiteit Amsterdam (VU) | fax : +31 - 20 - 598 - 7653 |
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-- 
Thilo Kielmann                                 http://www.cs.vu.nl/~kielmann/