Trait cssparser::AtRuleParser
[−]
[src]
pub trait AtRuleParser { type Prelude; type AtRule; fn parse_prelude(&self, name: &str, input: &mut Parser) -> Result<AtRuleType<Self::Prelude, Self::AtRule>, ()> { ... } fn parse_block(&self, prelude: Self::Prelude, input: &mut Parser) -> Result<Self::AtRule, ()> { ... } fn rule_without_block(&self, prelude: Self::Prelude) -> Self::AtRule { ... } }
A trait to provide various parsing of at-rules.
For example, there could be different implementations for top-level at-rules
(@media
, @font-face
, …)
and for page-margin rules inside @page
.
Default implementations that reject all at-rules are provided,
so that impl AtRuleParser<(), ()> for ... {}
can be used
for using DeclarationListParser
to parse a declartions list with only qualified rules.
Associated Types
type Prelude
The intermediate representation of an at-rule prelude.
type AtRule
The finished representation of an at-rule.
Provided Methods
fn parse_prelude(&self, name: &str, input: &mut Parser) -> Result<AtRuleType<Self::Prelude, Self::AtRule>, ()>
Parse the prelude of an at-rule with the given name
.
Return the representation of the prelude and the type of at-rule,
or Err(())
to ignore the entire at-rule as invalid.
See AtRuleType
’s documentation for the return value.
The prelude is the part after the at-keyword
and before the ;
semicolon or { /* ... */ }
block.
At-rule name matching should be case-insensitive in the ASCII range.
This can be done with std::ascii::Ascii::eq_ignore_ascii_case
,
or with the match_ignore_ascii_case!
macro.
The given input
is a "delimited" parser
that ends wherever the prelude should end.
(Before the next semicolon, the next {
, or the end of the current block.)
fn parse_block(&self, prelude: Self::Prelude, input: &mut Parser) -> Result<Self::AtRule, ()>
Parse the content of a { /* ... */ }
block for the body of the at-rule.
Return the finished representation of the at-rule
as returned by RuleListParser::next
or DeclarationListParser::next
,
or Err(())
to ignore the entire at-rule as invalid.
This is only called when parse_prelude
returned WithBlock
or OptionalBlock
,
and a block was indeed found following the prelude.
fn rule_without_block(&self, prelude: Self::Prelude) -> Self::AtRule
An OptionalBlock
prelude was followed by ;
.
Convert the prelude into the finished representation of the at-rule
as returned by RuleListParser::next
or DeclarationListParser::next
.