Re: Implementing character sets for Wide_Character

[Bob Duff <bobduff@theworld.com>]

Martin Trenkmann <martin.trenkmann@posteo.de> writes:

> I need to implement a containment check for Wide_Character in a wide
> character set. I have two approaches in mind.

If you really care about speed, then implement both and measure the
speed.  It's not clear that the bit map will be faster -- using more
memory harms cache behavior.

Also take a look at package Ada.Strings.Wide_Maps.
It contains type Wide_Character_Set, represented as a sorted
sequence of ranges.  Measure that one, too.

Another possibility is an array of pointers to bit maps,
with "null" in place of "all-False".

It all depends on what kinds of sets you're going to create,
and what operations you need to do.

Why Wide_Character rather than Wide_Wide_Character?

- Bob