James M Snell wrote: > > Eric Scheid wrote: > >> pub:control as a wrapper allows for order of control instructions to be >> preserved. Most often that won't be needed, but consider an entry whose >> content is an image POSTed from a mobile phone... order might be >> important, >> why rule it out? >> >> > I'm not sure I follow your mobile phone example but you're right, order > *might* be important. But can we honestly claim that it *might* be > significant in 80% of the cases or are we talking about a few nebulous > edge cases that fall somewhere in the 20% range? Sure, let's not rule > it out, but the Atom format does allow extensions to declare that order > is significant within those extensions, so we would not be ruling it by > not providing a pub:control container in the core. > > Is order significance of control elements the only argument we have left > in favor of pub:control?
We went over metadata v directives a while back and agreed (I thought) that there was some overlap but there's value in preserving a distinction. These are qualitatively distinct data we're talking about and I don't think that fact that we can put them the same place structurally in the entry obscure that. Again as a datapoint, I'll mention out that XML itself makes the distinction between markup and processing directives. >From a 'modelling' perspective I guess it makes no difference where control data lives. It's all markup. >From a programming perspective it does. It's cleaner to be able to pull out the directives in one shot, distinct from the other metadata because fom a programming perspective you're likely have different code for dealing with entry metadata which-are-metadata and entry-medata which-are-PIs. It would suck if we made pipelined XML processing and node iteration awkward. Hence I find this XPath compelling: atom:entry/pub:control as it lowers code entropy and general spaghettiness! Incidentally there's also the question of layering between data and control in the protocol. If we weren't tied into a mindset of "single XML document", I'd be up for sending control data alongside the entry instead of littering the entry with protocol stuff. I guess this would be a MIMEish position. cheers Bill
