Okay, utilizing the code suggested above, I get the expected behaviour. If I change the if-statement to the following, I get the errors noted further below. 
#!/usr/bin/perl

my $s = 'Tue Feb  8 11:11:11 2005: blah blah blah';

my $regex = '^$wday $mon\s+$mday \d{2}:\d{2}:\d{2} $year:';
my $wday = 'Tue';
my $mon = 'Feb';
my $mday = '8';
my $year = '2005';

findString($s);

sub findString($) {
    my $line = shift;

#   print "found\n" if $line =~ eval "qr/$regex/";
    if ($line =~ eval "qr/$regex/") {
        print "found\n";
    }
}

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Do the following errors make sense? Yes, I'm using Perl 5.005, but I cannot change this at this point. 
Scalar found where operator expected at (eval 1) line 1, at end of lin
+e
        (Missing operator before ?)
Backslash found where operator expected at (eval 1) line 1, near "$mon
+\"
        (Missing operator before \?)
found

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Placing curly braces around the qr() string pacifies the interpreter, but I no longer see the expected answer. Thanks for any insight.

In reply to Re^2: string substitution within regular expressions? by Anonymous Monk
in thread string substitution within regular expressions? by Anonymous Monk

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