Selectors which start with one colon, e.g. More...

#include "donner/css/selectors/PseudoClassSelector.h"

Collaboration diagram for donner::css::PseudoClassSelector:

Classes
struct	PseudoMatchResult
	Result of matches, returns if the selector matched and if it can be treated as a "primary" matcher. More...

Public Member Functions
	PseudoClassSelector (const RcString &ident)
	Create a PseudoClassSelector with the given ident.
	~PseudoClassSelector () noexcept
	Destructor.
	PseudoClassSelector (PseudoClassSelector &&) noexcept
	Move constructor.
PseudoClassSelector &	operator= (PseudoClassSelector &&) noexcept
	Move assignment operator.
	PseudoClassSelector (const PseudoClassSelector &other)
	Copy constructor.
PseudoClassSelector &	operator= (const PseudoClassSelector &other)
	Copy assignment operator.
bool	isValid () const
	Returns true if this selector is valid and supported by this implementation.
template<ElementLike T>
PseudoMatchResult	matches (const T &element, const SelectorMatchOptions< T > &options) const
	Returns true if the provided element matches this selector.
Specificity::ABC	computeSpecificity () const
	Compute the pseudo-class's specificity, using the rules from https://www.w3.org/TR/2022/WD-selectors-4-20221111/#specificity-rules.

Public Attributes
RcString	ident
	The name of the pseudo-class.
std::optional< std::vector< ComponentValue > >	argsIfFunction
	The arguments of the pseudo-class, if it is a function.
std::optional< AnbValue >	anbValueIfAnb
	The An+B value of the pseudo-class, for An+B pseudo-classes such as :nth-child.
std::unique_ptr< Selector >	selector
	The selector of the pseudo-class, for pseudo-classes such as :is() and :not(), or :nth-child(An+B of S).

Friends
std::ostream &	operator<< (std::ostream &os, const PseudoClassSelector &obj)
	Ostream output operator for PseudoClassSelector, outputs a debug string e.g. PseudoClassSelector(after).

Detailed Description

Selectors which start with one colon, e.g.

:nth-child(), are called pseudo-classes, and they represent additional state information not directly present in the document tree.

Each pseudo-class selector has a unique behavior.

Selectors supported:

:nth-child(An+B [of S]) - Selects the element if its index within its parent is An+B (1-based) when counting from the first element that would be selected by S. If S is omitted, the selector matches only elements that are direct children of their parent.
:nth-last-child(An+B [of S]) - Selects the element if its index within its parent is An+B (1-based) when counting from the last element that would be selected by S. If S is omitted, the selector matches only elements that are direct children of their parent.
:nth-of-type(An+B) - Selects the element if its index within its parent's children of the same type is An+B (1-based).
:nth-last-of-type(An+B) - Selects the element if its index within its parent's children of the same type is An+B (1-based).
:first-child - Selects the element if it is the first child of its parent.
:last-child - Selects the element if it is the last child of its parent.
:first-of-type - Selects the element if it is the first child of its parent and its type is the same as its parent.
:last-of-type - Selects the element if it is the last child of its parent and its type is the same as its parent.
:only-child - Selects the element if it is the only child of its parent.
:only-of-type - Selects the element if it is the only child of its parent and its type is the same as its parent.
:empty - Selects the element if it has no children.
:root - Selects the element if it is the root of the document.
:is(S) - Selects the element if it matches any of the selectors in the argument list.
:not(S) - Selects the element if it does not match S.
:where(S) - Selects the element if it matches all of the selectors in the argument list.

Not yet implemented, see https://github.com/jwmcglynn/donner/issues/3:

:has(S) - Selects the element if any of its descendants match S.
:defined - Selects if the element is supported by the user agent (donner svg in this case).

Pseudo-classes are defined in the following specs:

Linguistic Pseudo-classes, such as :dir() and :lang(), https://www.w3.org/TR/selectors-4/#linguistic-pseudos
Location Pseudo-classes, such as :link and :visited, https://www.w3.org/TR/selectors-4/#location
User Action Pseudo-classes, such as :hover and :active, https://www.w3.org/TR/selectors-4/#useraction-pseudos
Time-dimensional Pseudo-classes, such as :current and :past, https://www.w3.org/TR/selectors-4/#time-pseudos
Resource State Pseudo-classes, such as :playing and :muted, https://www.w3.org/TR/selectors-4/#resource-pseudos
Element Display State Pseudo-classes, such as :open and :fullscreen, https://www.w3.org/TR/selectors-4/#display-state-pseudos
Input Pseudo-classes, such as :enabled and :checked, https://www.w3.org/TR/selectors-4/#input-pseudos
Tree-Structural Pseudo-classes, such as :empty and :nth-child(), https://www.w3.org/TR/selectors-4/#structural-pseudos

Constructor & Destructor Documentation

◆ PseudoClassSelector()

donner::css::PseudoClassSelector::PseudoClassSelector ( const RcString & ident )

explicit

Create a PseudoClassSelector with the given ident.

Parameters

ident The name of the pseudo-class.

Member Function Documentation

◆ isValid()

bool donner::css::PseudoClassSelector::isValid ( ) const

inline

Returns true if this selector is valid and supported by this implementation.

See also: https://www.w3.org/TR/selectors-4/#invalid

◆ matches()

template<ElementLike T>

PseudoClassSelector::PseudoMatchResult donner::css::PseudoClassSelector::matches	(	const T &	element,
		const SelectorMatchOptions< T > &	options ) const

Returns true if the provided element matches this selector.

Template Parameters

T	A type that fulfills the ElementLike concept, to enable traversing the tree to match the selector.

Parameters

element	The element to check.
options	The options to use when matching

The documentation for this struct was generated from the following files:

donner/css/selectors/PseudoClassSelector.h
donner/css/Selector.h
donner/css/selectors/PseudoClassSelector.cc

Classes

Public Member Functions