bug#15625: 24.2.50; ebnf2ps generates bad postscript when ebnf-production-name-p is nil

[Michael Gauland]

When ebnf-production-name-p is nil, ebnf-eps-buffer should generate a 
diagram without the production name.

Instead, it generates an invalid file; evince hangs when trying to open 
it.

I believe the approporiate fix is to modfiy the BOP function in the 
postscript file to drop the prodcution name when it is blank.

The attached dribble file (started with emacs -Q), demonstrates:
1. Loading ebnf2ps
2. Writing a grammar rule.
3. Running ebnf-eps-buffer to generate ebnf--sequence.eps; this file is 
valid.
4. Setting ebnf-production-name-p to nil.
5. Running ebnf-eps-buffer again; now ebnf--sequence.eps is invalid.
6. Modifying ebnf2ps.el as described above.
7. Reloading ebfn2ps.el.
8. Running ebnf-eps-buffer yet again; now ebnf--sequence.eps is valid, 
and correctly omits the production name from the diagram.

I've also tested this on GNU Emacs 23.4.1 (i486-pc-linux-gnu, GTK+ 
Version 2.24.10) on Debian stable.
Kind Regards,
Mike Gauland


In GNU Emacs 24.2.50.1 (i386-mingw-nt6.1.7601)
 of 2012-08-25 on YAMALOK
Windowing system distributor `Microsoft Corp.', version 6.1.7601
Configured using:
 `configure --with-gcc (4.7) --cflags -m32 -O2 -g0 -march=prescott
 -mtune=prescott -pipe -IC:/gnuwin32/emacs/include
 -IC:/gnuwin32/emacs/lib -IC:/gnuwin32/src -IC:/gnutls/include
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ebnf-dribble
Description: Binary data