Re: TreeWalker.whatToShow

> Yes, but not so much, because filters are not inherited in iterators.
> You may attach one filter to different iterators.  In disabling the
> filter you are changing the behavior of every iterator.

That's true in Javascript, which is not very OO and forces you to write
filters as pointer-to-function. In languages such as Java, the disable
could be done on a per-instance basis of the filter object... so that the
disable could be shared when that object is shared, and disjunct when
separate instances were used.

> So in my view it would be a minor, very
> easy to implement, and useful addition to the Iterator's interfaces.

Allowing a filter-disable mechanism on Iterator has all the same issues as
making the iterator's filter attribute mutable. The WG decided against
doing so in Level 2. We can reconsider it in Level 3.

Joe Kesselman  / IBM Research

Received on Tuesday, 29 February 2000 09:59:51 UTC