demerphq wrote: > So assuming we want to add new modifiers (we kinda do) how should this > be addressed? Both going forward and dealing with legacy code.
My first inclination is that what you want is a way to get at the underlying structure of the regex so you can query what flags there are on it directly rather than relying on the string. I wave my hands in the direction of XS. Another option is to write a parser for qr strings to do the same thing. Or you can get sneaky. Since what you really want is a way to say "All the usual flags and things, plus $foo" you can compile a very simple regex and use that to divine the default flags and their order for the version of perl being run. Then you can do, a subtractive diff *observe the hands waving like so* to remove the defaults and leave only what you expect.
