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From: Stephen Cleary (shammah_at_[hidden])
Date: 2001-01-11 01:48:27

--- In boost_at_[hidden], "John E. Potter" <jpotter_at_f...> wrote:
> On Wed, 10 Jan 2001, Beman Dawes wrote:
> > I've been thinking about sequence algorithms because of several
> > boost postings, and string algorithms because I've seen several
nice onces
> > recently.

> How about algorithms templated on containers? That would open the
> door for many different ideas. Much different from the stl style.

No reason why we couldn't have our own algorithms library. I like
the idea. copy_if could be a prospective member, too.

What *I* would like to see, though, is more efficient binary-search-
style algorithms (lower_bound, binary_search, etc). The problem is
that the STL definitions force them to use op< or an equivalent
Pred. These can be made more efficient in some cases through the use
of a Unary Fobj that returns int: <0 if a<b, 0 if a==b, and >0 if a>b
(similar to strcmp/memcmp). This is especially a savings if the
comparision is expensive (such as long, similar strings).

I've written binary_search using this type of Unary Fobj (which I
call CompareAll), and the other algorithms should be similar. Tests
indicate that it is indeed faster for comparing strings.

I haven't tried timing the difference when used with arithmetic
types, though. On the old TODO list...


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