[metapost] input command

[mskala at ansuz.sooke.bc.ca]

On Sat, 8 Apr 2023, Toby Thurston wrote:

> "You are right that the Metapost manual (mpman.pdf) does *not* explain
> the "input" operation properly.

Its omission from the formal grammar seems to be an error.  The start of
Appendix B does mention that some features are not explained because
they're not of much interest, and readers should read the METAFONT book
for details.  The "let" command seems to fall into that category, being
listed in the table of commands, the formal grammar, and the index, but
nowhere else in the Metapost manual.  I think that "input"'s use in
example code shows it may actually be of interest to Metapost users after
all, but at the very least it could get as much mention as "let."

-- 
Matthew Skala
mskala at ansuz.sooke.bc.ca                 People before tribes.
https://ansuz.sooke.bc.ca/