Re: Is there a lex utility for Ada that handles unicode?

["Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de>]

On 27 Oct 2005 10:17:15 -0700, brian.b.mcguinness@lmco.com wrote:

> Is there some equivalent of the lex utility that produces
> Ada code rather than C code, and is capable of handling
> any character in the Unicode basic code plane?  I am
> thinking of using it on strings read from a GUI created
> with GtkAda, so it would probably be best if it accepted
> UTF-8 strings, but I could convert the input to a wide
> string if necessary.

Why do you wish to convert it to wide? You can parse UTF-8 encoded text
as-is. After all that was the idea behind UTF-8. For example, my unit
compiler parses directly UTF-8. The advantage is that I can use the same
parser for units spelt both in pure ASCII and in full UTF-8. I simply flag
UTF-8 tokens from the table if I don't want to recognize them. There is a
trick that 8-bit tokes need to be replaced with 2-characters UTF-8
equivalents. But they are rare. BTW, the parser is table-driven, so I don't
need lex.

For UTF-8 handing in Ada you can take a look at:
http://www.dmitry-kazakov.de/ada/strings_edit.htm

It and table-driven parsers in Ada are included in components:
http://www.dmitry-kazakov.de/ada/components.htm

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de