Multiple same qualifiers of same type?

[zvr]

The specification does not currently say anything about restricting qualifiers to single appearance.

For example, can a single SWHID have two origin qualifiers?

Do we need some wording that each one appears at maximum once? Or some of them, and other may appear multiple times?

[zacchiro]

Nice catch, thanks

Conceptually: we have always considered each qualifier to be unique, and not to be repeated.

In terms of formal specification, I think that at some point we were sort-of-convinced that the SWHID URI-based syntax was implicitly excluding parameter repetition.
But I'm no longer sure about that (and I haven't double checked).

And in any event I think it would be much better to state explicitly that qualifiers must not be repeated.

[rdicosmo]

Indeed, very good point! The current grammar allows repeated qualifiers, see:

specification/Chapters/4.Syntax.md

Lines 27 to 31 in 8b75455

	<qualifiers> := ";" <qualifier> [ <qualifiers> ] ;
	<qualifier> ::=
	<context_qualifier>
	| <fragment_qualifier>
	;

#38 clarifies that each qualifier can occur at most once.

[rdicosmo]

This is now addressed in #38