Hi Jonathan,
Jonathan Mayer schrieb:
>
> Apologies for butting in where my opinion is not asked for, but ...
>
you're welcome, it's a mailing list, isn't it.
> > statement: A! | B! | C | D
> >
> > is so easy to understand: At least A and B, optionally C and/or D
> > but without ORDER, in comparison to action codes and greps and maps
> > and line noise.
>
> At what point does "A!" become mandatory? In the
> block: statement(s) /* A or B must be part of block */
> construct? Or in the
> program: block(s) /* A or B must be part of program */
> block: statement(s)
> construct? There are times whem both forms are useful -- but defining
> "mandatory" as part of the syntax for the singular "statement"
> construct is limitting.
hmmm, what is wrong when it is necessary for the block statement, because
then it is automatically true for program
>
> Also, what if the programmer wants a more complicated logical function
> on the set of statements that comprises a "minimal" block?
>
> It seems to me, P:RD already has the functionality you desire, in a
> much more flexible form. What's wrong with:
>
> statement: A | B | C | D
> block: "{" statements(s) "}"
> {
> /* some code to test for the presense of A and B,
> else return undef */
> }
syntax is scattered between grammar rules and action code and the
presense check isn't always so intuitive as in this primitive example.
A and B are also complex subrules and it is really only a question
of style.
>
> I'd hate to see P:RD fall into same trap as regexps: P:RD doesn't need
> to be a complete programming language. P:RD is fine as a perl
> accessory.
yes it's really fine, even it it stays as it already is.
Regards
Charly
--
Karl Gaissmaier Computing Center,University of Ulm,Germany
Email:[EMAIL PROTECTED] Network Administration
Tel.: ++49 731 50-22499
