Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!cwjcc!hal!ncoast!allbery
From: allbery@ncoast.ORG (Brandon S. Allbery)
Newsgroups: comp.text
Subject: Re: What features would you like in GNU troff?
Message-ID: <13759@ncoast.ORG>
Date: 16 Jun 89 23:04:49 GMT
References: <JJC.89May31220314@jclark.UUCP> <742@dtscp1.UUCP> <10959@orstcs.CS.ORST.EDU> <21@nx32s.anduk.co.uk> <762@dtscp1.UUCP> <25@nx32s.anduk.co.uk>
Reply-To: allbery@ncoast.ORG (Brandon S. Allbery)
Followup-To: comp.text
Distribution: comp
Organization: Cleveland Public Access UN*X, Cleveland, Oh
Lines: 22

As quoted from <25@nx32s.anduk.co.uk> by lee@anduk.co.uk (Liam R. Quin):
+---------------
| Also, your high-school arithmetic (whatever that may be) is flawed, 
| because ( and . are not possible in the first character of a name, and
| nearly 100 names are pre-defined.  On the other hand, some control
| characters are allowed....
+---------------

Beg pardon, but the only restriction I've found is that ( can not be used as
a single-character name; it is possible to define a macro called ".F", for
instance, and call it as "..F".  I've not found a need to define "." as a
macro, but it could be useful e.g. to monitor memory usage as you define
macros, since troff will not only stop defining at .., it will execute the
macro called "." if it exists; make "." do a ".pm" for a quick memory-usage
debug check.  (Or ".rn pm .".)

++Brandon
-- 
Brandon S. Allbery, moderator of comp.sources.misc	     allbery@ncoast.org
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