John--

The eq operator looks for an exact match of the left and right value, whilst the =~ operator checks to see if the string on the left contains the regular expression on the right side.

The problem is that the string you're using contains characters in it that have special meaning when they're inside a regular expression. In this case, these are the parenthesis. For your regular expression argument, try escaping the special characters, like so: 
perl -e '$a="MIN.(NERR_VOL2)"; $b="MIN.\(NERR_VOL2\)" ; $x = ( qq/$a/ 
+=~ qq/$b/ ) ; print "$a == $b ? $x \n" ;'

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You'll want to read the 'perlre' documentation to see what's going on here.

Note 1: There's another character in the expression that has special meaning in your regular expression, but it didn't hurt you in this case.

Note 2: Another thing: You should never assign a variable like so: 
$b = "$a";

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You're telling perl to create a string, and since it has an expression inside the string, you're telling it to interpolate the value. The end result is that you're asking Perl to do a lot more work to get the result you really want: 
$b = $a;

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which tells Perl to simply copy the value of $a into $b.

--roboticus

In reply to Re: Matching quoted variables. Cant make it work.. by roboticus
in thread Matching quoted variables. Cant make it work.. by johntweed

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