Patrick, Jan, Thanks for the explanation. Pity that, I **did** like the idea of putting IE only stuff inside square brackets! At least I feel reasonably happy using the underscore now!
:-) Bob McClelland, Cornwall (U.K.) www.gwelanmor-internet.co.uk ----- Original Message ----- From: "Patrick H. Lauke" <[EMAIL PROTECTED]> To: <[email protected]> Sent: Saturday, April 02, 2005 9:16 PM Subject: Re: [WSG] underscore hack - why underscore? > designer wrote: > > I have been playing with the underscore hack and noticed that almost > > anything that isn't 0-1 or a-z performs the same trick. > [...] > > Is this very naughty? It doesn't validate as CSS, but then neither does the > > underscore hack (unless the validator is wrong, as some would have us > > believe). > > > > So what's the story here? > > Look at the CSS2.1 spec's section on syntax and keywords > http://www.w3.org/TR/CSS21/syndata.html#keywords > > "In CSS2.1, identifiers may begin with '-' (dash) or '_' (underscore). > Keywords and property names, beginning with -' or '_' are reserved for > vendor-specific extensions." > > "An initial dash or underscore is guaranteed never to be used in a > property or keyword by any current or future level of CSS. Thus typical > CSS implementations may not recognize such properties and may ignore > them according to the rules for handling parsing errors. However, > because the ***initial dash or underscore is part of the grammar***, > CSS2.1 implementers should always be able to use a CSS-conforming > parser, whether or not they support any vendor-specific extensions." > (emphasis mine) > > So, as per spec, the underscore can "legally" be used. Other characters > are just syntax errors. > As for the validators: they're correct in that anything prefixed with > underscore is invalid in the light of the official W3C CSS spec (as it > implies vendor specific properties which go outside of the spec), but > that doesn't mean that the underscore isn't legal in the wider context > of CSS grammar (while, again, other characters are both outside of spec > *and* break the grammar rules) > > -- > Patrick H. Lauke > _____________________________________________________ > re·dux (adj.): brought back; returned. used postpositively > [latin : re-, re- + dux, leader; see duke.] > www.splintered.co.uk | www.photographia.co.uk > http://redux.deviantart.com > > ****************************************************** > The discussion list for http://webstandardsgroup.org/ > > See http://webstandardsgroup.org/mail/guidelines.cfm > for some hints on posting to the list & getting help > ****************************************************** > > > ****************************************************** The discussion list for http://webstandardsgroup.org/ See http://webstandardsgroup.org/mail/guidelines.cfm for some hints on posting to the list & getting help ******************************************************
