[tex-k] Bug in METAFONT(book)

[Sebastian Miele]

Hello!

I may have found a bug in grayf.mf that is not already fixed in
systems/knuth/dist on CTAN (neither in mfbook.tex nor in grayf.mf). In
the file something gets prepended to extra_chars without including a
space at the end:

  if mg>1: hppp := hppp*mg; vppp := vppp*mg;
   extra_endchar:=
    "if charcode>0:currentpicture:=currentpicture scaled mg;fi"
    & extra_endchar; fi;

Hence, METAFONT on a file like

  font_identifier "GRAYBUG";
  mag:=2;
  extra_endchar := "if false: fi";
  input grayf

yields errors.

Best wishes
Sebastian