[whatwg] [html5] window.print() undefined

[Matthew Raymond]

Sjoerd Visscher wrote:
> Matthew Raymond wrote:
>>   I know this isn't how you meant it, but this all seems a bit user
>>hostile. The user sees something on the screen he/she wants to print,
>>but an event is called at the last minute that changes the content to
>>something else before the user can print. So if I select the part of the
>>page you want to "undo" and tried to print the selection, I'd get a
>>blank page? And in theory, the entire page could be hidden. Sounds like
>>print-specific DRM to me.
> 
> You can do that with css anyway, what is your point?

   That CSS can be overridden by the user stylesheet?

> Every browser feature adds opportunities to both help and annoy the 
> user, but please let is be up to [the] web developer to act responsible 
> with the features he has available. Who wants to annoy the customer anyway?

   Businesses annoy customers all the time, but that's beside the point.
If all HTML content is semantic rather than presentational, what is the
purpose of not displaying it in a specific media? We're not talking
about media-specific presentation (since CSS+XBL handles that nicely).
We're talking about media-specific content.

   The only reason I can think of for such control is if you're using
the web app like a word processor or something and you want to print the
document but not the UI. In that situation, it may be better to simply
allow the web developer to copy the document contents into a separate
document object, then manipulate and print the content from that
document separately. This allows the same effect as the before and after
print events without tampering with the browser's normal print
mechanism. You just clone the document, modify the clone at will, print
it and destroy it. The web app should never hijack the behavior of a
common browser function.