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The "ishanjayawardena/scd_proposal" page has been changed by ishanjayawardena.
http://wiki.apache.org/xerces/ishanjayawardena/scd_proposal?action=diff&rev1=8&rev2=9

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{{{http://example.org/schemas/po.xsd#xmlns(p=http://example.com/schema/po)xscd(/type::p:USAddress)}}}<<BR>>
  In here, {{{xmlns(p=http://example.com/schema/po)xscd(/type::p:USAddress)}}} 
represents an RSCD. The W3C SCD specification consists of a more comprehensive 
set of examples[[#7|[7] ]][[#8|[8] ]][[#9|[9] ]] that illustrates a number of 
possible usages and types of SCDs/SCPs.<<BR>>
  
- Please note that the term ''assembled schema'' (or ''schema'' or ''the schema 
description schema component'') refers to a resulting logical namespace that is 
generated by the combination of one or more such schemas and these schemas may 
be physically represented as schema documents. In Xerces, the schema 
description schema component(i.e. the XML schema object model) is represented 
by the XSModel[[#10|[10] ]] interface and the schema components are represented 
by the org.apache.xerces.xs interfaces.<<BR>>
+ Please note that the term ''assembled schema'' (or ''schema'' or ''the schema 
description schema component'') refers to a logical graph of schema components 
and these schemas may be physically represented as schema documents. In Xerces, 
the schema description schema component(i.e. the XML schema object model) is 
represented by the XSModel[[#10|[10] ]] interface and the schema components are 
represented by the org.apache.xerces.xs interfaces.<<BR>>
  
+ In this project, I am focusing only on implementing the RSCD support for 
Xerces because according to the feedback I received from the Xerces community, 
it will often be more difficult and less useful to work with ASCDs given that 
there is no standard way to identify a schema by dereferencing a URI. The 
ability to resolve (i.e. to parse and evaluate) an RSCD comes from the ability 
to resolve a given SCP relative to a given context (i.e. either relative to a 
schema or to a schema component). Therefore, giving Xerces the ability to 
resolve SCPs (more specifically, non-canonical SCPs) is the main objective of 
this project and the RSCD support is implemented as a feature which uses it. 
There are couple of compelling reasons behind this.<<BR>>
- In this project, I am focusing only on implementing the RSCD support for 
Xerces because according to the feedback I received from the Xerces community, 
it will often be more difficult and less useful to work with ASCDs since there 
is no defined way to resolve a URI to a schema. For example, consider the first 
ASCD that I have mentioned. It is obvious that if we try to evaluate that ASCD 
against the schema in that URI, first we have to resolve that URI and build a 
schema from it, which is not possible with Xerces. Even the W3C specification 
does not specify any convention to build a schema by referring to such URI. 
Therefore it will be much more appropriate to implement only the RSCD support 
for Xerces.<<BR>>
- 
- The ability to resolve (i.e. to parse and evaluate) an RSCD comes from the 
ability to resolve a given SCP relative to a given context (i.e. either 
relative to a schema or to a schema component). Therefore, giving Xerces the 
ability to resolve SCPs (more specifically, non-canonical SCPs) is the main 
objective of this project and the RSCD support is implemented as a feature 
which uses it. There are couple of compelling reasons behind this.<<BR>>
  
   1. SCP is the main component in any ASCD or RSCD(but we are only interested 
in RSCDs)<<BR>>
  

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