how do i use a regex that is in a string

my script looks in a file and may return a line that contains a regular expression.

something like s/a/b/g
So i know have a $ which contains the above regex.

Is it possible to use that string as a regular expression on another string.

eg

$a = "aaabbbaaa";
$b = "s/b/c/g";

$a =~$b;

That obviously doesnt work but you see what i'm trying to do.

Thanks

Mark

In reply to using a regex which is in a string by monkyMonk

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