I can't help but think japhy's right, but...
(?i-xsm:\s+[a-z][a-z]\+[a-z][a-z]\s+\(\d\d\)\d\d) look at all those repeated elements! yeck.
here's a rework which allows the use of {n}, or optionally (add a true parameter when calling the script) breaks all groups down into \d+ or [a-z]+ groups. Finally, double checks that the produced pattern does match the original string... I was pondering making some handler for \W characters, but that's probably too much for such a tchotchke... 
$anynum=$ARGV[0];
chomp($orig=<STDIN>);
$i = quotemeta($orig);
$i=~ s/[a-z]/l/g;
$i =~ s/\d/n/g;
while ($i=~/(l+)/g){
    if ($anynum) {
        $i=~s/($1)/'[a-z]+'/e;        
    } else {
        $i=~s/($1)/"[a-z]{".length ($1)."}"/e;
    }
}
while ($i=~/(n+)/g){
    if ($anynum) {
        $i=~s/($1)/"\\d+"/e;        
    } else {
        $i=~s/($1)/"\\d{".length ($1)."}"/e;
    }
}
$i=~s/\s+/s\+/g;
$i=qr/$i/;
print "pattern is : $i\n";
print $orig=~/$i/; #double check

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In reply to Re: Deriving Regular Expressions (boo) by boo_radley
in thread Deriving Regular Expressions by mojotoad

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