Perl: strings and brackets

["Leonard den Ottolander" <leonardjo hetnet nl>]

		Hi!

 Is this expected behaviour when using brackets inside a perl string? The 
following script returns

Found 'A(-1)' in 'A-1'
Found 'A(-1)' in 'A-1'
Found 'A[-1]' in 'A-1'
Found 'A[-1]' in 'A-1'
Found 'A(-1)' in 'A-1'

(Observed with perl 5.005 on RH 6.2 and 5.6.0 on RH 7.0.)

#!/usr/bin/perl

$A = 'A(-1)';
$B = "A\(-1\)";
$C = 'A[-1]';
$D = "A\[-1\]";
$E = "A\x28-1\x29";
$_ = 'A-1';

#print "Content-type: text/plain\n\n";
if (/$A/) { print "Found \'$A\' in \'$_\'\n";}
if (/$B/) { print "Found \'$B\' in \'$_\'\n";}
if (/$C/) { print "Found \'$C\' in \'$_\'\n";}
if (/$D/) { print "Found \'$D\' in \'$_\'\n";}
if (/$E/) { print "Found \'$E\' in \'$_\'\n";}

					Bye,

					Leonard.