JSON-LD Framing requires "@type"?

Dear JSON-LD folks,

(CC affected Annotation and SocialWeb WGs)

At TPAC last year, there was discussion that led to the recommendation of
aliasing @id and @type to "id" and "type", if that is possible given
existing json keys and structure.  For the Social Web WG and Annotation WG,
we have followed this recommendation for our current JSON-LD based specs.

An issue generated for the Annotation group [1] was to provide JSON-LD
frames to make it easier for developers to produce the required layout.  In
working on that, it seems that the framing algorithm _requires_ @type, and
does not process the context looking for aliases.  Is that true and
intentional?

An example in the playground:  http://tinyurl.com/hqsphco
And the same result is obtained using the Python implementation.

To make both implementations work, I need to use @type in both the input
graph and the frame document, despite the alias being present in the
referenced (and processed) context doc.

Bug? Seems like a show-stopper for providing frames?

Rob

[1] https://github.com/w3c/web-annotation/issues/80

-- 
Rob Sanderson
Information Standards Advocate
Digital Library Systems and Services
Stanford, CA 94305