Re: [boost] Report from Berlin C++ Standards Committee meeting

From: Reece Dunn (msclrhd_at_[hidden])
Date: 2006-04-11 08:48:25

David Abrahams wrote:
> "Reece Dunn" <msclrhd_at_[hidden]> writes:
> 
> > Drawing influence from Python, I suggest that the non-throwing version look like:
> >
> >    std::pair<T,bool> string_to<T>(x)
> >
> > allowing:
> >
> >    fn( string_to<Object>(object).first );
> 
> How does that draw influence from Python?

I was refering to multiple-valued returns. For example:

   def string_to( object ):
      return object, was_there_an_error

   obj, err = string_to( ... )

> That interface doesn't allow for types that can't be default
> constructed.
> 
>   optional<T> string_to<T>(x)
> 
> seems more likely.

That does look better. So in that case, an error would be indicated by the optional<T> return containing null.

- Reece
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