Re: [Groff] eqn converts "lambda" to "&lamda;"

[Ingo Schwarze]

Hi Brian,

McGuinness, Brian wrote on Sun, Dec 13, 2015 at 07:15:21PM -0500:

> I was experimenting with eqn because I think it
> will prove very useful for generating MathML
> code easily.

Groff is certainly a good choice for processing eqn(1)
input, in particular when aiming for typeset output,
for example PostScript or PDF.
I haven't experimented with GNU eqn MathML output, though.

For converting eqn input to MathML output, you might also
wish to look at mandoc as an alternative: http://mdocml.bsd.lv/
It may or may not be sufficient or better for your purpose,
and i would be interested in any feedback.

One thing that may or may not be relevant for your use case is
speed.  Here are example numbers from my OpenBSD-current system:

  $ cd /usr/X11R6/man/man3/
  $ time eqn -TMathML glMultMatrix.3 | groff -man -Txhtml > /dev/null 2>&1
 0m17.67s real     0m15.92s user     0m01.45s system
  $ time mandoc -Thtml glMultMatrix.3 > /dev/null
 0m00.00s real     0m00.01s user     0m00.00s system
  $ time sh -c 'for f in `jot 1000`; do mandoc -Thtml glMultMatrix.3 \
    > /dev/null; done'
 0m07.25s real     0m02.83s user     0m03.33s system

Mandoc does HTML5 and MathML by default and does not need any options
or preprocessors.

Being faster by a factor of more than 2000 (two thousand)
may be relevant for some applications.

Yours,
  Ingo