[css-values] Get the URL of the current document

[hober]

One of the use cases for #6544 is to provide a QR code that, when scanned, would be the URL of the current document. But apparently there's no way to get the URL of the current document from CSS.

From #css today:

[18:33] <hober> Ooooh, very simple CSS question that I apparently don't         
                know the answer to: How can I, from CSS, get a URL to           
                the current document? Not the current stylesheet, the           
                current document. What to pass to url()?                        
[18:36] <cbiesinger> I didn't think that was possible                           
[18:39] <hober> oh, booo. filed                                                 
                https://github.com/w3c/csswg-drafts/issues/6546                 

[plinss]

Seems like something that would be useful in the content: of headers/footers of print style sheets as well.

[faceless2]

I can confirm it is very useful for print headers/footers - we use a non-standard env(location) for this. To fully cover most headers/footers you'd also need another env() to retrieve the current date.

[Crissov]

Which of these would have the same value?

• https://example.com/foo.bar?quuz=baz#lorem
• http://example.com/foo.bar?quuz=baz#lorem
• https://example.com/foo.bar?quuz=bak#lorem
• https://example.com/foo.bar?quuz=baz
• https://example.com/foo.bar#lorem
• https://example.com/xyz/../foo.bar?quuz=baz#lorem
• https://example.com//foo.bar?quuz=baz#lorem
• https://example.com/foo.bar?quuz=baz#lorem
• https://example.com/foo?quuz=baz#lorem
• https://me@example.com/foo.bar?quuz=baz#lorem
• https://me:***@example.com/foo.bar?quuz=baz#lorem

[tabatkins]

The function might want some options to control what shows up, but I assume that by default we'd use the scheme, domain, path, and query, ignoring the credentials and hash.