🚀 go-pugleaf

Sorry about following up on my own postings, but noone else did and I
did find at least a partial solution.

In <1993Jan20.161638.7096@uts.uni-c.dk> kubipdal@uts.uni-c.dk (Peter Dalg}rd) writes:

>a) How would one know that \bffam is the family corresponding to
>	\mathbf{} (In fact it is, but suppose I wanted do it for
>	another alphabet)?

>b) Math alphabets do not seem to be defined unless there is reference 
>	to them in a formula (??) As it is now, $X_i$ gives me an
>	error that textfont 4 is undefined, but $X_i+\mathbf{z}$
>	works. How do I enforce definition of the relevant fonts?

Part b) is easily disposed of by creating a dummy formula with a font
selection inside, e.g.
\setbox0\hbox{$\mathbf\relax$}

Part a) is tricky. If the math alphabet has been created with 
\new@internalmathalphabet or \newmathalphabet, then the control
sequence expands to something that starts with a call to 
\select@group, whose second argument is the math family that I
was after. The first argument is the command sequence itself.
(I.e. \mathbf ->\select@group \mathbf \bffam ....)
So I need to extract the third token of the expansion of the
math alphabet control sequence. I ended up with this (setfam is my
original macro):

\newcount\h@ckedf@mily
\def \getthirdtoken#1#2#3#4***{#3}
\def \@wfulf@milyh@ck#1{
        \h@ckedf@mily\expandafter\getthirdtoken#1***
        \setbox0\hbox{$#1\relax$}
}
\def \mathletter#1#2{
        \@wfulf@milyh@ck{#1}
        \setfam{\h@ckedf@mily}{#2}
}
\def \bfmathletter#1{\mathletter{\mathbf}{#1}}

This doesn't work for rm and mi since they are set up differently
in newlfont.sty. However, they are in their usual places, so one can
just:

\def \mimathletter#1{\setfam 1 {#1}}
\def \rmmathletter#1{\setfam 0 {#1}}

Something tells me that this can't be the right way, but it's the best
I can do!

	Peter

PS: Please note that I routinely \catcode RET SPC and TAB to 9 (ignored)
in my macros, people who prefer the usual TeX style need to delete a few
spaces and insert some % signs in various places.