Re: boolean attributes case-sensitivity (detailed review of Semantics)

On Jul 17, 2007, at 4:03 PM, Simon Pieters wrote:

>
> (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 different.

My guess at a rationale would be that the boolean value needs to  
match the boolean attribute case sensitively. We could take a  
different approach, but I could see why the draft has it that way.  
This would explain why boolean attributes are different than other  
attributes too (the values are case-sensitively matching the  
attribute name which is specified as lowercase).

Take care,
Rob