[css-syntax-3][cssom-1] Accept <relative-selector-list> in top-level style rules

[cdoublev]

I suspect this has already been discussed before but I cannot find any trace of it.

If I am not mistaken, & is valid in the prelude of a top-level style rule and represents :root. So it is theoretically valid to use a <relative-selector-list> like > body.

Would it be acceptable to define the prelude of top-level style rules with <relative-selector-list> instead of <selector-list>?

If so, changes would be required in CSS Syntax 3 (8.1. Defining Block Contents: the <declaration-list>, <rule-list>, and <stylesheet> productions) and CSSOM (parse a selector and serialize a selector).

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Obviously, that does not seem usefull. I am actually interested in having a single style rule definition to simplify the representation of CSS rule definitions.

The block value of @scope is defined with <stylesheet>, which accepts all CSS rules except those excluded by @scope or restricted to a specific context (eg. keyframe, margin, etc).

For all other CSS rules whose block value is <stylesheet>, this is equivalent to accepting all top-level rules excluding @import and @namespace.

But the prelude of (scoped) style rules in @scope is defined with <relative-selector-list> (like nested style rules) therefore valid rules in @scope need to be explicitly defined rather than defining a list of excluded rules, which is otherwise matching the intent of the formal definition of <stylesheet> in CSS Syntax 3 (emphasize added):

For rules that use <stylesheet>, all rules are allowed by default, but the spec for the rule may define what types of rules are invalid inside the rule.

the <stylesheet> production represents a list of rules. It is identical to , except that blocks using it default to accepting all rules that aren’t otherwise limited to a particular context.

https://drafts.csswg.org/css-syntax-3/#declaration-rule-list

[romainmenke]

This was previously discussed here : #8010
But that was more from an author perspective.

[cdoublev]

Ah, I knew it, but failed to find it... Thanks. and I agree with your opinion/decision.