Renji added the comment:
I through "forward reference" is "\1 (abcd)". Not "some sort of reference in
second repetition to data from first repetition".
Ok. In other words refers from on repetition to other supported, but with
purely formal restrictions. And
Renji added the comment:
In my example reference and capture group presents in two difference
alternatives. They don't follow each other, but executed in random order. If
this don't supported in one case, why it supported in
New submission from Renji :
I can compile "((a)|b\2)*" expression and this expression successfully return
captures from first repetition and second repetition in one time. But if I
write (b\2|(a))* expression, I get "invalid group reference 2 at position 3"
error. Ei
