You wouldn't need to use xsl:choose for that. An ordinary XPath expression like /a/subvertex[xmi:type='b'] would work, assuming you were interested in getting a list of subvertex elements. And assuming you had the xmi namespace declared.
And yes, you could use that in the match attribute of an xml:template element. Generally it's better (i.e. more in tune with the XSL language) to do that than to use procedural elements like xsl:for-each.
What is that? Is that a mongol hoarde? Can we fend them off with this tiny ad?
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