23 Feb
2021
23 Feb
'21
2:47 a.m.
I can imagine a simple perl (or python or whatever)
script that would run
through groff input [and] determine which preprocessors are actually
needed ...
Brian imagined such and implemented it way back when. Though I used
it, I've forgotten its name. One probably could have fooled it by
tricks like calling pic only in a .so file and perhaps renaming .so.
But I never heard of it failing in real life. It does impose an extra
pass over the input, but may well save a pass compared to the
defensive groff -pet that I often use or to the rerun necessary when I
forget to mention some or all of the filters.
23 Feb
23 Feb
10:42 a.m.
On Feb 23, 2021, at 3:47, M Douglas McIlroy
<m.douglas.mcilroy(a)dartmouth.edu> wrote:
If I remember correctly, it was an awk script printing out the
suggested pipeline to use. One could then cut and paste that line.
jaap
I can imagine a simple perl (or python or
whatever) script that would run
through groff input [and] determine which preprocessors are actually
needed ...
Brian imagined such and implemented it way back when. Though I used
it, I've forgotten its name. One probably could have fooled it by
tricks like calling pic only in a .so file and perhaps renaming .so.
But I never heard of it failing in real life. It does impose an extra
pass over the input, but may well save a pass compared to the
defensive groff -pet that I often use or to the rerun necessary when I
forget to mention some or all of the filters. 
1:23 p.m.
#!/bin/rc
# doctype: synthesize proper command line for troff
troff=troff
eqn=eqn
prefer=prefer
opt=''
dev=''
while(~ $1 -*){
switch($1){
case -n;
troff=nroff
eqn=neqn
prefer='prefer -n'
case -T
dev=$1
case -*
opt=$opt' $1'
}
shift
}
ifs='
'{
files=`{echo $*}
}
grep -h
'\$LIST|\|reference|Jp|^\.(EQ|TS|\[|PS|IS|GS|G1|GD|PP|BM|LP|BP|PI|cstart|begin|TH...|TI)|^\.P$'
$* |
sort -u |
awk '
BEGIN { files = "'$"files'" }
/\$LIST/ { e++ }
/^\.PP/ { ms++ }
/^\.LP/ { ms++ }
/^\.EQ/ { eqn++ }
/^\.TS/ { tbl++ }
/^\.PS/ { pic++ }
/^\.IS/ { ideal++ }
/^\.GS/ { tped++ }
/^\.G1/ { grap++; pic++ }
/^\.GD/ { dag++; pic++ }
/^\.\[/ { refer++ }
/\|reference/ { prefer++ }
/^\.cstart/ { chem++; pic++ }
/^\.begin +dformat/ { dformat++; pic++ }
/^\.TH.../ { man++ }
/^\.BM/ { lbits++ }
/^\.P$/ { mm++ }
/^\.BP/ { pictures++ }
/^\.PI/ { pictures++ }
/^\.TI/ { mcs++ }
/^\.ft *Jp|\\f\(Jp/ { nihongo++ }
END {
x = ""
if (refer) {
if (e) x = "refer/refer -e " files " | "
else x = "refer/refer " files "| "
files = ""
}
else if (prefer) { x = "cat " files "| '$prefer'| "; files
= "" }
if (tped) { x = x "tped " files " | "; files = "" }
if (dag) { x = x "dag " files " | "; files = "" }
if (ideal) { x = x "ideal -q " files " | "; files = "" }
if (grap) { x = x "grap " files " | "; files = "" }
if (chem) { x = x "chem " files " | "; files = "" }
if (dformat) { x = x "dformat " files " | "; files = "" }
if (pic) { x = x "pic " files " | "; files = "" }
if (tbl) { x = x "tbl " files " | "; files = "" }
if (eqn) { x = x "'$eqn' '$dev' " files " | ";
files = "" }
x = x "'$troff' "
if (man) x = x "-man"
else if (ms) x = x "-ms"
else if (mm) x = x "-mm"
if (mcs) x = x " -mcs"
if (lbits) x = x " -mbits"
if (pictures) x = x " -mpictures"
if (nihongo) x = x " -mnihongo"
x = x " '$opt' '$dev' " files
print x
}'
On Feb 23, 2021, at 5:42 AM, Jaap Akkerhuis
<jaapna(a)xs4all.nl> wrote:
On Feb 23, 2021, at 3:47, M Douglas McIlroy
<m.douglas.mcilroy(a)dartmouth.edu> wrote:
If I remember correctly, it was an awk script printing out the
suggested pipeline to use. One could then cut and paste that line.
jaap I can imagine a simple perl (or python or
whatever) script that would run
through groff input [and] determine which preprocessors are actually
needed ...
Brian imagined such and implemented it way back when. Though I used
it, I've forgotten its name. One probably could have fooled it by
tricks like calling pic only in a .so file and perhaps renaming .so.
But I never heard of it failing in real life. It does impose an extra
pass over the input, but may well save a pass compared to the
defensive groff -pet that I often use or to the rerun necessary when I
forget to mention some or all of the filters. 
1:49 p.m.
Hi Doug,
Was it ‘doctype’? That's what it's called in Kernighan & Pike's ‘Unix
Programming Environment’, pp. 306-8. Groff had something similar called
grog(1) which had flaws when I rewrote it in sh and mainly awk back
in 2002. (My version never made it in because an FSF copyright
assignment was required and their answers to some of my questions meant
I wouldn't sign.) Someone else since rewrote Groff's in Perl.
I can imagine
a simple perl (or python or whatever) script that
would run through groff input [and] determine which preprocessors
are actually needed ...
Brian imagined such and implemented it way back when. Though I used
it, I've forgotten its name. defensive groff -pet that I often use
I've taken to putting the information needed as a comment at the start
of the main source file whence it's picked up by a generic run-off
script. Similar to man(1) looking for a «'\"» comment with code
letters: ‘p’ for pic, ‘v’ for vgrind, etc.
--
Cheers, Ralph.
1165
days inactive
1165
days old
3 comments
4 participants
participants (4)
-
Brantley Coile -
Jaap Akkerhuis -
M Douglas McIlroy -
Ralph Corderoy