Re: String filtering

[David Trudgett <wpower@zeta.org.au.nospamplease>]

Jacob Sparre Andersen <sparre@nbi.dk> writes:

>    procedure Strip_Non_Alphanumeric (Str : in out Unbounded_String) is
>       --  This version does in-place modification of the unbounded
>       --  string, and is thus actually making use of Str being an
>       --  unbounded string and not a fixed length string.
>       Position : Natural := 1;
>    begin
>       while Position =< Length (Str) loop
>          if Is_In (Element (Str, Position), Alpha_Num_Space_Set) then
>             Position := Position + 1;
>          else
>             Delete (Source  => Str,
>                     From    => Position,
>                     Through => Position);
>          end if;
>       end loop;
>    end Strip_Non_Alphanumeric;
>

Yes, that works, too, and I've added it in just for completeness.
Thanks. (Your =< should have been <= though. There's always something
to fix, isn't there? ;-))


>
> Good.  It makes the String and Unbounded_String versions practically
> equivalent - probably both in CPU and memory use.

Much of a muchness, I would guess. Profiling particular applications
on particular compilers is the only way to tell for sure, though.


Thanks for your help, Jacob.

David


-- 

David Trudgett
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