Enum selectors::parser::Component

pub enum Component<Impl: SelectorImpl> {
    Combinator(Combinator),
    ExplicitAnyNamespace,
    ExplicitNoNamespace,
    DefaultNamespace(Impl::NamespaceUrl),
    Namespace(Impl::NamespacePrefix, Impl::NamespaceUrl),
    ExplicitUniversalType,
    LocalName(LocalName<Impl>),
    ID(Impl::Identifier),
    Class(Impl::Identifier),
    AttributeInNoNamespaceExists {
        local_name: Impl::LocalName,
        local_name_lower: Impl::LocalName,
    },
    AttributeInNoNamespace {
        local_name: Impl::LocalName,
        operator: AttrSelectorOperator,
        value: Impl::AttrValue,
        case_sensitivity: ParsedCaseSensitivity,
        never_matches: bool,
    },
    AttributeOther(Box<AttrSelectorWithOptionalNamespace<Impl>>),
    Negation(Box<[Selector<Impl>]>),
    FirstChild,
    LastChild,
    OnlyChild,
    Root,
    Empty,
    Scope,
    NthChild(i32, i32),
    NthLastChild(i32, i32),
    NthOfType(i32, i32),
    NthLastOfType(i32, i32),
    FirstOfType,
    LastOfType,
    OnlyOfType,
    NonTSPseudoClass(Impl::NonTSPseudoClass),
    Slotted(Selector<Impl>),
    Part(Box<[Impl::Identifier]>),
    Host(Option<Selector<Impl>>),
    Where(Box<[Selector<Impl>]>),
    Is(Box<[Selector<Impl>]>),
    PseudoElement(Impl::PseudoElement),
}

A CSS simple selector or combinator. We store both in the same enum for optimal packing and cache performance, see [1].

[1] https://bugzilla.mozilla.org/show_bug.cgi?id=1357973

Variants

Combinator(Combinator)

ExplicitAnyNamespace

ExplicitNoNamespace

DefaultNamespace(Impl::NamespaceUrl)

Namespace(Impl::NamespacePrefix, Impl::NamespaceUrl)

ExplicitUniversalType

LocalName(LocalName<Impl>)

ID(Impl::Identifier)

Class(Impl::Identifier)

AttributeInNoNamespaceExists

Fields of AttributeInNoNamespaceExists

local_name: Impl::LocalNamelocal_name_lower: Impl::LocalName

AttributeInNoNamespace

Fields of AttributeInNoNamespace

local_name: Impl::LocalNameoperator: AttrSelectorOperatorvalue: Impl::AttrValuecase_sensitivity: ParsedCaseSensitivitynever_matches: bool

AttributeOther(Box<AttrSelectorWithOptionalNamespace<Impl>>)

Negation(Box<[Selector<Impl>]>)

Pseudo-classes

FirstChild

LastChild

OnlyChild

Root

Empty

Scope

NthChild(i32, i32)

NthLastChild(i32, i32)

NthOfType(i32, i32)

NthLastOfType(i32, i32)

FirstOfType

LastOfType

OnlyOfType

NonTSPseudoClass(Impl::NonTSPseudoClass)

Slotted(Selector<Impl>)

The ::slotted() pseudo-element:

https://drafts.csswg.org/css-scoping/#slotted-pseudo

The selector here is a compound selector, that is, no combinators.

NOTE(emilio): This should support a list of selectors, but as of this writing no other browser does, and that allows them to put ::slotted() in the rule hash, so we do that too.

See https://github.com/w3c/csswg-drafts/issues/2158

Part(Box<[Impl::Identifier]>)

The ::part pseudo-element. https://drafts.csswg.org/css-shadow-parts/#part

Host(Option<Selector<Impl>>)

The :host pseudo-class:

https://drafts.csswg.org/css-scoping/#host-selector

NOTE(emilio): This should support a list of selectors, but as of this writing no other browser does, and that allows them to put :host() in the rule hash, so we do that too.

See https://github.com/w3c/csswg-drafts/issues/2158

Where(Box<[Selector<Impl>]>)

The :where pseudo-class.

https://drafts.csswg.org/selectors/#zero-matches

The inner argument is conceptually a SelectorList, but we move the selectors to the heap to keep Component small.

Is(Box<[Selector<Impl>]>)

The :is pseudo-class.

https://drafts.csswg.org/selectors/#matches-pseudo

Same comment as above re. the argument.

PseudoElement(Impl::PseudoElement)

An implementation-dependent pseudo-element selector.

Implementations

impl<Impl: SelectorImpl> Component<Impl>

pub fn is_combinator(&self) -> bool

Returns true if this is a combinator.

pub fn as_combinator(&self) -> Option<Combinator>

Returns the value as a combinator if applicable, None otherwise.

pub fn maybe_allowed_after_pseudo_element(&self) -> bool

Whether this component is valid after a pseudo-element. Only intended for sanity-checking.

pub fn visit<V>(&self, visitor: &mut V) -> bool where
    V: SelectorVisitor<Impl = Impl>, 

Trait Implementations

impl<Impl: Clone + SelectorImpl> Clone for Component<Impl> where
    Impl::NamespaceUrl: Clone,
    Impl::NamespacePrefix: Clone,
    Impl::NamespaceUrl: Clone,
    Impl::Identifier: Clone,
    Impl::Identifier: Clone,
    Impl::LocalName: Clone,
    Impl::LocalName: Clone,
    Impl::LocalName: Clone,
    Impl::AttrValue: Clone,
    Impl::NonTSPseudoClass: Clone,
    Impl::Identifier: Clone,
    Impl::PseudoElement: Clone, 

fn clone(&self) -> Component<Impl>

Returns a copy of the value.

pub fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<Impl: SelectorImpl> Debug for Component<Impl>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<Impl: Eq + SelectorImpl> Eq for Component<Impl> where
    Impl::NamespaceUrl: Eq,
    Impl::NamespacePrefix: Eq,
    Impl::NamespaceUrl: Eq,
    Impl::Identifier: Eq,
    Impl::Identifier: Eq,
    Impl::LocalName: Eq,
    Impl::LocalName: Eq,
    Impl::LocalName: Eq,
    Impl::AttrValue: Eq,
    Impl::NonTSPseudoClass: Eq,
    Impl::Identifier: Eq,
    Impl::PseudoElement: Eq, 

impl<Impl: PartialEq + SelectorImpl> PartialEq<Component<Impl>> for Component<Impl> where
    Impl::NamespaceUrl: PartialEq,
    Impl::NamespacePrefix: PartialEq,
    Impl::NamespaceUrl: PartialEq,
    Impl::Identifier: PartialEq,
    Impl::Identifier: PartialEq,
    Impl::LocalName: PartialEq,
    Impl::LocalName: PartialEq,
    Impl::LocalName: PartialEq,
    Impl::AttrValue: PartialEq,
    Impl::NonTSPseudoClass: PartialEq,
    Impl::Identifier: PartialEq,
    Impl::PseudoElement: PartialEq, 

fn eq(&self, other: &Component<Impl>) -> bool

This method tests for self and other values to be equal, and is used by ==.

fn ne(&self, other: &Component<Impl>) -> bool

This method tests for !=.

impl<Impl: SelectorImpl> StructuralEq for Component<Impl>

impl<Impl: SelectorImpl> StructuralPartialEq for Component<Impl>

impl<Impl: SelectorImpl> ToCss for Component<Impl>

fn to_css<W>(&self, dest: &mut W) -> Result where
    W: Write, 

Serialize self in CSS syntax, writing to dest.

pub fn to_css_string(&self) -> String

Serialize self in CSS syntax and return a string.