I've been brushing up on the <guide> element
part of the OPF spec since I'm adding this functionality to Sigil, and from my understanding of it, it can have several <reference> elements with the same type.
That makes no sense to me.
How can a book have several Lists of Illustration, or several indices or several title pages? Sure, I could imagine an omnibus of sorts needing this, but it still seems... weird.
What I find particularly puzzling is that guide part of the spec IMHO seems to be written with the assumption that there can be no such duplicates. The description of the "text" type states:
Quote:
|
First "real" page of content (e.g. "Chapter 1")
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So there can hardly be more than one of these, since the Reading Systems wouldn't be able to tell which of the multiples to show to the user as "the first real page of content". Also, other parts of the spec that allow duplication of semantics (like, say, multiple author metadata) have this possibility
explicitly stated. There is no such statement for the guide <reference> elements.
Clearly, since the spec doesn't forbid it, it is allowed. What I'm interested in is whether this is a good idea. Honestly, I don't think it is.
And the least you could say about that part of the spec is that it should have a statement eliminating the ambiguity.
I'm interested in what others think about this.