A derived type such as xs:byte may always be used in XQuery, but may not be used in a basic XSLT system. xq2xsl translates xs:byte(88) to
itself if running on a schema aware system
xq:integer(88,-128,127) where xq:integer is a stylesheet defined function that checks that the first argument is an xs:integer
within the specified range, when xs:byte is being used as a function.
xs:integer(88) in contexts where a sequence type is required.