[XeTeX] Overline in xetex using polyglossia

[Yusuf Mitha]

I have just started using polyglosia last week. I dont know if it an
issue or there is a work around. In Englis text if I use {$\overline
{test}$}, the word gets overlines. However If I do it to Arabic texts.
It just dissapears.

Is there a way to implement the \eamph command for overlining arabic
texts just like arabxetex?

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Yusuf Mitha