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
I've an alternation where some subrules are mandatory but others are
optional (Subrule statement).
This doesnt make much sense to me. An alternation is a rule that can be
matched by any _one_ of a selection of rules. So that means you can't say
that some of those alternations are
yes that's what I want. I know that the solution could be the
permutation of the pieces but this blows up the grammar with n!.
Sure does... :-)
however, what you're talking about is a semantic validation
of input,
something which usally happens after parsing and hence isn't dealt
Karl Gaissmaier wrote:
some suggestions for additional features of Parse::RecDescent, specifically
the ability to specify required alternatives within a repeated subrule:
statement: A! | B! | C | D
and mutually exclusive alternations:
rule : A ^ B ^ C
The problem with these
