Re: [Freefont-bugs] ligatures

[Karl Berry]

    But...these, I think, have their own internal idea of which
    replacements to do.

In the case of TeX, the ligatures are completely controlled by the TFM
file.  That information comes from the metrics that come with the
original font, so whatever you specify would, ultimately, be used.

    It looks like many apps that will do obligatory replacements, simply
    ignore the discretionary ones. 

Not surprising.  I wouldn't want an application to treat `st' and `ffi'
the same, which is where we came in ...

    Could it be there is no standard policy as to how apps should handle
    these tables?

Even if there is a "standard" policy written down somewhere (I don't
know of any myself), I would venture to say that there are plenty of
applications that do whatever the heck they feel like.

It sounds like what would work best in practice is to specify the
ligatures we actually want to be used, like ffi, as obligatory, even if
they may not be obligatory in a natural language sense.  Whereas marking
ones we don't want to be used "by default", like st, to be
discretionary.

Cheers,
k