wrong ligatures in ae and ze tt fonts

[Hilmar Schlegel]

Sebastian Rahtz schrieb:
> 
> Lars =?iso-8859-1?Q?Hellstr=F6m?= writes:
>  > I'm not so sure it is questionable (anymore; I too thought it was when I
>  > wrote the monowidth/typewriter comments in the v1.9 fontinst sources). The
>  > main problem is that `--' _is_ allowed input for generating an endash in
>  > the T1 encoding, and hence all fonts with that encoding should work like
>  > that. It is not very useful for typewriter fonts (LaTeX's \verb and
>  > verbatim do a bunch of special declarations to escape these ligatures), but
>  > it is nontheless a standard in the encoding.
 
> and indeed, that shows the mess Knuth got us into, by mixing so many
> concepts in a single place. the LaTeX hacks to escape the ligatures in
> verbatim are too horrid to use in general, and Knuth does not let us
> change font ligatures at the macro level. When I typeset XML with TeX,

I think the misconception is the lack of a distinctive attribute of
verbatim (input? output?) "typewriter" fonts (encodings) on the one hand
side and on the other hand side monospaced "typewriter" fonts.
You can see this in fontinst when it comes to encoding variants which
ckeck either for "\tty" or "monowidth". Actually a monospaced font has
nothing to do with a typewriter face. So therefore a strict definition
of a monospaced encoding without spacing-modifying ligatures (e.g. -- >
-) would be in place. On the other hand side there is also a "variable"
width typewriter face quite handy. This could have changing width caused
by ligatures and/or simply by proportional character metrics.

For many purposes at hand a strict verbatim monowidth font is necessary
but a \vt (instead of \tt) font with ligatures could be useful for
in-text typewriter elements.

> I definitely dont ever ever want these ligatures to happen, but I
> cannot do anything about it, short of making the characters
> permanently active.  Yuck.

Better to use fontinst to make a monowidth version...

> 
> ah well.
> 

Well!

Hilmar Schlegel
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