Re: Implementing character sets for Wide_Character

[Bob Duff <bobduff@theworld.com>]

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

> Thanks for pointing out that both methods may consume the same amount of
> memory. So at the end it's up to the compiler and caching effects which version
> runs faster. 

Compilers can do all sorts of things, which is one reason why it's wise
to measure.

But I doubt any Ada compiler would generate a jump table for the case
statement you showed in your OP.  That would be a 2**16-entry table with
almost all of the entries duplicated.  I'd expect something more like a
subtract, a compare, and a conditional jump.  And the function should be
inlined.

> ...At the meantime, however, I was made aware of package
> Ada.Strings.Wide_Maps that I will use now.

And keep using it, unless you discover efficiency problems.  ;-)

- Bob