ErikCorryGoogle

I like that names have to be unique.  Some regexp flavours allow dupes and unify the storage between them,
but that feels complicated and difficult to spec. For something like this:
/(<foo>..)((<foo>..))*/
normally you would reset the capture whenever you iterate the *-loop, but it would be strange to delete the
foo capture on entering the loop, or would it?

By putting the named captures on the match object as properties, you are preventing any future standard from
ever adding a new property to the Match object, ever, since it might conflict with the name of a named capture.
Perhaps it makes more sense to add a .map property to the match of type Map and have string keys on that map.
This also avoids the question of what happens if someone makes a named capture called __proto__ or prototype.