I've been working on the DFDL spec quite a bit. Steve Hanson suggested that this woudl be good to have in the document before the April OGF.

5. What is DFDL, including a sub-section giving scope of DFDL 1.0.

Right now the doc has this content which is pretty much entirely TBD/placeholder.

Can someone step up to the plate to revise this? I am working on other aspects than this, i.e., trying to reorganize and straighten out the decomposition of the semantics into the parse function and parse strategies. I really want to focus on this aspect, but I agree with steve that thsi woudl be great to have done in time.

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What is DFDL Version 1.0?

Version 1.0 of DFDL is a language capable of expressing a wide array of binary and text-based data formats.

DFDL is capable of describing binary data as found in the data structures of Cobol, C, PL1, Fortran, etc. In particular, it is able to describe repeating sub-arrays where the length of an array is stored in another location of the structure.

TBD....

DFDL is capable of describing a wide variety of textual data formats. These include TBD:list of examples.

TBD: mixtures. Composition properties. I.e., two formats can be nested, concatenated, etc. to create a new working format definition. (limitations here due to regexp?)

The following topics have been deferred to future versions of the standard:

Extensibility: There are real examples of proprietary data format description languages that we use as our base of experience from which to derive standard DFDL. However, there are no examples of extensible format description languages; hence, while extensibility is desirable in DFDL, there is not yet a base of experience with extensibility from which to derive a standard.

Layering: Some formats require data to be described in multiple layers. That is, where one element's contents becomes the representation of another element. DFDL V1.0 allows description of only one layer.