I have some trouble understanding just what the proposal is, since the
RFC doesn't contain any examples. But I gather that you want to usurp
*both* the (...) and the [...] notation for numeric ranges.
This would change the meaning of any code that happened to contain a
regex like this:
/(12.3,45.67)/
That seems to me like a very bad idea.
Usurping /[...]/ isn't quite as awful an idea, since patterns like
/[12,34]/ are probably rare.
The behavior you want is already possible without an extension:
/(\d+\.?\d*) # look for a number
(?
(?{$1 < 37.3 || $1 > 200}) # If it's out of range
(?!) # ...then backtrack
)
/x
I agree that this isn't really pretty, but
1. the proposed notation is really nasty, since it overloads existing
well-established notations, and
2. I think a better response would be to find a way to use the
existing features with a prettier notation, since they are much
more generally applicable than your proposed extension.
