Revised diagram following today's discussions

As usual, no guarantees I've got this right. . .

Changes since last time [1]:

 1) Added Param Signature and Param;
 2) Added Step Container and used it;

Known bugs:

 1) We agreed to rename 'Signature' as 'Type' (or 'Component Type');
 2) Pipelines don't have Signatures.

    A generalisation I'm missing is that any given kind of Step has a
    constant Signature across all instances, but each instance of a
    Step Container has its own Signature.  Also not _sure_ the
    Signatures are the same in the two cases. . .

    I don't know how to do Class-level properties in UML. . .

ht

[1] http://lists.w3.org/Archives/Public/public-xml-processing-model-wg/2006Aug/0096.html



-- 
 Henry S. Thompson, HCRC Language Technology Group, University of Edinburgh
                     Half-time member of W3C Team
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