[whatwg] <time>

[Christoph Päper]

Mikko Rantalainen:
> How about specifying that the content of <time> element will be parsed
> for the date only if 'datetime' attribute is empty. In addition, the
> spec should explicitly say that if the content is time in any other
> calendar system but Proleptic Gregorian calendar then the datetime  
> MUST
> contain equivalent time in standard format (...).

 From an author's perspective the simplest thing would be a mutable | 
datetime| attribute: it contains either an ISO 8601 datetime (i.e.  
proleptic Gregorian, preferably including time spans and lesser  
precision than days, e.g. weeks) or an alphabetic identifier of the  
calendar system used in the text node. Only if the attribute contents  
is purely alphabetic and known user agents may try to parse the  
textual contents. Perhaps the default value, only used when the  
attribute is left out, could be (proleptic) Gregorian and hence also  
trigger parsing of the textual content. Authors are encouraged to  
supply the standard date nevertheless, because parsers for other  
calendars may be more error-prone or not even implemented.

 From a reader's perspective dates should never be autoconverted  
inline, by the way. They should be converted for purposes other than  
reading the text, though.