New feature in v3: cast!

[Brian Candler]

On Mon, May 13, 2013 at 08:49:44AM +0100, Brian Candler wrote:
>   - assignment or comparison where the RHS is a string but the LHS is an
>     attribute with a non-string value causes the RHS to be converted to the
>     type of the LHS (at parse-time if both LHS and RHS are constants,
>     otherwise can be deferred to run-time)

This is also a reason to implement list qualifiers:

   if (reply:Session-Time < 100)

allows us to know the type of the LHS, whereas

   if ("%{reply:Session-Time}" < 100)

is just a string of characters.