Yaron Koren wrote:
I do believe, though, that the thing that prevents a simpler storage format is the need for translation. Without it, a template parameter can be defined by a simple set of values: a label, a description, an input type, and then a handful of modifiers for the input type (like the list of allowed values, if it's a radiobutton or dropdown). If translation of different values is allowed, though, you really need the structure that XML provides, or else the whole thing devolves into chaos.
Most wikis won't require translation, though; and that includes most Wikimedia projects - they're in one language at a time. The one big exception is Wikimedia Commons, which also happens to be the proposed first usage of this template-call-editing system. And for that site, translation really is necessary (I think).
So, at the risk of complicating things even further - maybe it makes sense to have a split approach - one format that handles translation, another that doesn't? The non-translation format, given that it would be simpler, could even be embedded directly in the template - possibly within a <documentation> tag in the template, as Platonides suggested.
There could be <documentation lang="en">, <documentation lang="fr">, <documentation lang="de">...