An ack or grep regex to match two lines, that are nearly the same

Question

I'm looking in our code for something that looks very much like:

#$foo="bar";
$foo="baz";

Problems:

1. I don't know the name of the variable
2. I don't know which line is actually commented out.
3. I really don't seem to be able to properly write a multi-line regex.

My initial attempt was ack /\$(.\*)=.\*$\$($1)=/

I prefer ack usually for code grepping, but I don't mind using grep either. JWZ probably thinks I have way more than 2 problems by now.

Answer 1

Neither grep nor ack will handle more than one line at a time.