Gunther Rademacher <grd@gmx.net> asked me to raise this: he reported difficulty registering for bugzilla.

<quote>
     The addition of FunctionTest to the sequence type syntax
     causes an ambiguity for occurrence indicators, because the
     grammar allows an optional occurrence indicator both
     at the end of a FunctionTest, and following a FunctionTest.

     Though the occurrence-indicators constraint assigns them
     precedence over other uses of the respective symbols, I
     can't see that it regulates the FunctionTest problem - both
     alternatives clearly would provide the SequenceType context
     (hope I didn't miss something...).
</quote>

MHK observation: The spec says "It is permitted to use parentheses to enclose item types, in order to resolve ambiguities that could arise from the OccurrenceIndicator of a SequenceType." - but it doesn't say what the interpretation is if you don't use parentheses. It should make it clear that

function () as xs:string *

means

function () as (xs:string *)

rather than

(function () as xs:string) *