[XeTeX] XeTeX (/not/ XeLaTeX) : Marginal kerning, font protrusion, hyperlinks

[Philip Taylor]

Further to this thread, in a document on which I am currently
working I have to write :

> \XeTeXprotrudechars = 2
> \rpcode \fd /hyphen = 250
> \rpcode \fd /period = 150

I would like to write :

> \XeTeXprotrudechars = 2
> \rpcode \fd `\- = 250
> \rpcode \fd `\. = 150

or at worst :

> \XeTeXprotrudechars = 2
> \rpcode \fd \TeXtoUnicode `\- = 250
> \rpcode \fd \TeXtoUnicode `\. = 150

Clearly there /is/ a reason why the first was not /
cannot be implemented, but (a) what is that reason,
and (b) does \TeXtoUnicode already exist, and if
not, are there complexities in implementing it which
I have not foreseen ?

Philip Taylor