[XeTeX] Getting completely the wrong glyphs when using characters from Latin Extended B

[Michiel Kamermans]

Philip,
> In an earlier thread (see below), Joanthan Kew said that string quotes 
> were necessary if one was trying
> to reference a TTF/OTF/Type-1 font rather than a TFM-based (TeX) 
> font.  How, then, does \setmainfont
> know whether I want a TTF/OTF/Type-1 font rather than a TFM-based 
> (TeX) font if I am not permitted to use quotation marks to indicate 
> that I want the former ?
The short answer is that \setmainfont is a fontspec command, and 
fontspec "knows what you want".

Jonathan's comments were regarding using the plain (Xe)TeX \font 
command. For the \font command, quotation marks are tremendously 
important. For fontspec, which adds the quotes for you when implicitly 
calling \font, adding quotes of your own will have detrimental effects: 
like Khaled says, it'll end up calling \font\somebinding=""font name"" 
(note the double double quotes =)

So it depends on what you want to interface with. Plain TeX: use quotes. 
Fontspec: no quotes (I try to stay away from \font as much as possible, 
since fontspec takes care of these matters).

- Mike