boolean attributes case-sensitivity (detailed review of Semantics)

(This is part of my detailed review of the Semantics and structure of HTML  
documents section.)

The spec says about boolean attributes:

    If the attribute is present, its value must either be the empty string
    or the attribute's canonical name, exactly, with no leading or trailing
    whitespace, and in lowercase.

The value was case-insensitive in HTML4. Additionally, keywords in  
enumerated attributes in HTML5 may use any mix of lower-case and uppercase  
letters. I don't see a good reason why boolean attributes should be  

Simon Pieters
Opera Software

Received on Tuesday, 17 July 2007 21:03:41 UTC