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From: flee@cs.psu.edu (Felix Lee)
Newsgroups: comp.lang.perl
Subject: Wordless Perl.
Message-ID: <p+1Gf#+e@cs.psu.edu>
Date: 4 Feb 91 19:20:24 GMT
References: <1991Feb4.163023.2980@uvaarpa.Virginia.EDU>
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Dale Worley wonders:
> Is there a non-trivial Perl program that consists entirely of
> punctuation marks?

Well, I can't think of a way to write a loop with only punctuation.
Worse, I can't find a way of generating output.  This is Perl's fatal
flaw: it requires you to use alphabetic characters.  True terseness
lies in hieroglyphic programming languages.

But if you'll allow the "-p" flag, here's "uniq":
	#!/usr/bin/perl -p
	$: = $_;
	/^$__$/ && ($_ = '');
	$__ = $:;

If you'll allow preprocessed input, here's a (very slow) spell checker.
	#!/usr/bin/perl -p
	/^-$/
	 ? (++$[, $_='')
	 : $[
	   ? (/^$/ || $_{$_}) && ($_ = '')
	   : ($_{$_}++, $_ = '');
Name it "spckrm" and use the following script:
	#!/bin/sh
	(cat /usr/dict/words
	 echo '-'
	 perl -pe 'tr/A-Z/a-z/;$_=join("\n",split(/[^a-z]+/))."\n"' ${1+"$@"}
	) | spckrm | sort -u

This is only scratching the surface of wordless Perl.  More complex
things are surely possible.
--
Felix Lee	flee@cs.psu.edu