[closed] Re: Versioning and nested declarations

Norman Walsh <ndw@nwalsh.com> writes:

> Is this allowed:
>
>   <p:declare-step ...>
>     <p:declare-step ...>
>       <p:import href="http://www.w3.org/2008/xproc-2.0.xpl"/>
>       ...
>     </p:declare-step>
>     ...
>   </p:declare-step>
>
> It seems to me that we could say it is allowed, and has the effect of
> making the entire pipeline use the 2.0 definitions, or we could say
> no, that if you want to use 2.0 definitions inside a nested pipeline
> (for example, one you've imported), then you have to also have the
> import for that library at the top level.
>
> It seems to me that the tricky part of allowing it is dealing with
> steps that you may already have parsed before you see the 2.0 import.
> E.g., what if you rejected them because they use new options defined
> in 2.0?
>
> On the whole, I think it might be safer to say that nested imports of
> new versions are only legal if the new version has already been
> imported.

The WG considered this issue and concluded that they would only say
that an implementation may raise an error if it encounters a nested
import of a versioning pipeline library.

                                        Be seeing you,
                                          norm

-- 
Norman Walsh <ndw@nwalsh.com> | The best people usually owe their
http://nwalsh.com/            | excellence to a combination of
                              | qualities which might have been
                              | supposed incompatible.--Bertrand Russell