This is a response to Bert Bos' review [1] of the Widgets 1.0 Requirements document [2].
1.1.2. Standardizable Aspects of a Widget
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COMMENT 11) Why aren't the UIDL and the programming language of the widgets among the standardizable aspects? If the MIME type defines just the packaging, the manifest and the metadata, then it doesn't actually tell you which runtime environment to launch, which conflicts with requirement R1.
To the list of standardizable aspects I have now added: "A pre-existing scripting language to provide widgets with functionality along with a set of language-independent programmable interfaces that could be implemented by widget engines and made available to widgets at runtime" and "a pre-existing language to declare the user interface." However, these will be marked as open issues. Although these are identified as standardizable aspects, we make no commitment at this point to standardising them in the Widgets 1.0 spec.
Also, although the packaging and manifest may later turn out to be useful on their own, the immediate need is for a complete widget format. The proprietary formats mentioned in the WD all define how to write actual widgets (but mutually incompatible ones).
True, specifying a complete solution for writing widgets would solve the mutual compatibility problem but might make the specification completely incompatible with every widget engine in the wild (however, because of fragmentation in the widget space, I acknowledge this may happen regardless). Also, the working group feels that specifying a complete solution for widgets may be beyond the scope of the charter. That is the reason that for Widgets 1.0 we are primarily focusing on things like packaging, automated updating, and bootstrapping.
In fact, R28 (see comment 28) requires ECMAScript and R22 (see comment 24) requires OOP, so it seems the WD does consider the programming language standardizable.
Our intention is to only state that the interfaces should be implementable in ECMAScript but don't go as far as to actually mandate ECMAScript. That said ECMAScript does seem to be one of the few congruent consistencies found across a number of widget engines. -- Marcos Caceres http://datadriven.com.au [1] http://lists.w3.org/Archives/Public/public-appformats/2007Feb/0131.html [2] http://www.w3.org/TR/2007/WD-widgets-reqs-20070209/
