RE: Positional predicates in pattern matching

> b[something][2] - match the 'b' which is the second sibling 
> 'b' if 'something' 
> evaluates to true. 
No, it is 'match the second sibling b for which "something" is true'. In
your case, something is always true, so it means "match the second sibling
b".

1. Take all the b's
2. remove those for which predicate 1 is false
3. take the 2nd of those that remain

Michael Kay