Why is this comparison only works for integer type id ?
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I am wondering does the statement `[@id=current()/@id]` can only work if the id is integer for example:

    <elem id="1">
    <elem id="1">

But if I have:

    <elem id="AAA">
    <elem id="AAA">

It does not work.

How to compare **string @id** in XSLT 2.0 ? 

Thanks.
Regards,
John