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From: eichin@apollo.com (Mark Eichin)
Newsgroups: comp.lang.perl
Subject: shouldn't backslash really quote?
Message-ID: <1991May22.175723.18174@uvaarpa.Virginia.EDU>
Date: 22 May 91 17:57:23 GMT
Sender: mmdf@uvaarpa.Virginia.EDU (Uvaarpa Mail System)
Reply-To: eichin@apollo.com
Organization: The Internet
Lines: 37

The script (at the end of this message) prints:

Line == <<x_$foo>>
found x-pat
found x-brace-dollar-pat

I would have expected it to print "found x-slash-dollar-pat" as well,
or at least threeslash... I get this output with VAX/BSD perl 3.041
and 4.000, as well as Apollo Domain/OS perl 4.003. (I really do want
pattern matching, not equality checking, and (as the last if clause
shows) I should really be able to do this without eval.) Can anyone
explain to me why I can't simply backslash a dollar sign, as is
implied by the info file, 
		"Simply quote all the non-alphanumeric characters:
			     $pattern =~ s/(\W)/\\$1/g;"

#!perl
$_='x_$foo';
$pat = "foo";
print "Line == <<$_>>\n";
if(/x_.$pat/) {
	print "found x-pat\n";
} 
if(/x_\$$pat/) {
	print "found x-slash-dollar-pat\n";
} 
if(/x_\\$$pat/) {
	print "found x-twoslash-dollar-pat\n";
} 
if(/x_\\\$$pat/) {
	print "found x-threeslash-dollar-pat\n";
} 
if(/x_[\$]$pat/) {
	print "found x-brace-dollar-pat\n";
} 
					_Mark_ <eichin@apollo.hp.com>
					CCD-East