Re: [boost] Re: 4 more associative containers.

From: Jeremy Maitin-Shepard (jbms_at_[hidden])
Date: 2004-02-03 15:32:08

"David B. Held" <dheld_at_[hidden]> writes:

> "Jeremy Maitin-Shepard" <jbms_at_[hidden]> wrote in message
> news:87u128yr3g.fsf_at_jbms.ath.cx...
>> I believe that a library named ``indexed_set,'' which has been
>> proposed and is pending formal review, provides this functionality
>> in addition to supporting multiple indices.

> Are you sure it does the same thing?  I was under the impression
> that Joaquin's library lets you define *additional* indexes, but what
> if you just want to use an existing index, but it is comparable to
> something other than the key_type?

I am pretty certain that the library supports that.  More commonly,
however, the comparison process can be separated into key extraction,
which obtains some key_type from the value_type, and then comparison on
the key_type; this separation is supported by the library.  I believe
that in most cases the desire for a comparison predicate which operates
on multiple types is actually (more conveniently) satisfied by being
able to specify the key_type alone, rather than a value_type.

-- 
Jeremy Maitin-Shepard