[XeTeX] Traditional TeX ligatures once again

[Jonathan Kew]

On 28 Jun 2007, at 4:40 pm, Alexej Kryukov wrote:

> As you can see, the proper mappings for "<<" and ">>" are not
> exclusively Cyrillic, and there are no other ligatures which would
> be specific for traditional TeX Cyrillic encodings (e. g. T2A).
> So, I don't think creating a special mapping just for Cyrillic-script
> users makes any sense: to my mind, adding these 2 sequences
> to tex-text would be much better. However, if tex-text is really
> intended to emulate just the behavior found in old CM fonts (and not
> DC, EC, etc.), then a new mapping is really needed, but it should be
> called not "tex-cyrillic", but rather "tex-t1", "tex-ec" or so.

I'm not particularly concerned that "tex-text" should correspond only  
to CM; that's just the starting point I used, being the default set  
of fonts in Plain TeX. But I realize most people are using LaTeX with  
newer encodings such as EC or others. So let's consider extending  
"tex-text" to support additional sequences. Are there any more  
besides << and >> that are used in one or other of the common font  
encodings? I'm not all that familiar with them, but I'm sure others  
here know the details....

JK