A general proposal for "multiple expressions" in Target, Prerequisite, Predicate: (trying to take into account previous remarks)

1- Target: this element is unique to a TA. But the target may be defined as a composition of several artifacts, that are in turn described by several expressions elements under <target>. It is this composition that is subject to the predicate.

See the example given in wiki (issue #2 http://wiki.oasis-open.org/tag/Issues) , where the target is a combination of "author" + related artifacts, identified using different - but related - XPath expressions :

<target> <prose>...</prose> <expr name="author" lg="XPath"

<expr name="books" lg="XPath">document(..mybooklist..)/book[@author = $author/name]</expr> <expr name="publishers" lg="XPath">document(..publishing houses ..) /publishersdirectory/publisher[fn:index-of( fn:distinct-values("for $bk in $books return $bk/@publisher"), @name) gt 0 ]</expr> </target> This combination of artifacts is subject to the TA predicate and prerequisite. 2. Prerequisite: this optional element may be multiple in a TA, with the implicit semantics of logical AND. But each one of these <prerequisite> elements is structured like above <target>: MAY contain several named expressions, that may be referred to by their name and composed into more complex logical expressions:

<prerequisite> <prose>...</prose> <expr name="youngauthor" lg="XPath" > (a boolean expression, e.g. age less 35) </expr> <expr name="prolific" lg="XPath"> ( a boolean expression, e.g. number books more than 10 over 10 years ) </expr> <expr name="international" lg="XPath"> ( a boolean expression, e.g. published in more than 2 languages )</expr> <expr name="primary" lg="XPath"> ( a boolean expression, that states the overall prereq expression, e.g.: $youngauthor and ($prolific or $international) </expr> </prerequisite>

3- Predicate: this element is unique to a TA. Structured exactly like a Prerequsite element above.

Jacques