donner::svg::Property< T, kCascade > Struct Template Reference

Holds a CSS property, which has a name and value, and integrates with inheritance to allow cascading values using the CSS model with specificity. More...

#include "donner/svg/properties/Property.h"

Collaboration diagram for donner::svg::Property< T, kCascade >:

Public Types
using	Type = T
	Type of the property value.

Public Member Functions
	Property (std::string_view name, GetInitialFn< T > getInitialFn=[]() -> std::optional< T > { return std::nullopt;})
	Property constructor, which is initially unset.
std::optional< T >	get () const
	Get the property value, without considering inheritance.
T	getRequired () const
	Gets the value of the property, requiring that the value is not std::nullopt.
const T &	getRequiredRef () const
	Gets a const-ref to the value, for accessing complex types without copying.
void	set (std::optional< T > newValue, css::Specificity newSpecificity)
	Set the property to a new value at the given specificity.
void	set (PropertyState newState, css::Specificity newSpecificity)
	Unset the current value and set the property to a specific state.
void	substitute (std::optional< T > newValue)
	Replace the current property's value with a new value at the current specificity.
void	clear ()
	Clear the current property's value.
Property< T, kCascade >	inheritFrom (const Property< T, kCascade > &parent, PropertyInheritOptions options=PropertyInheritOptions::All) const
	Inherit the property from the parent element, if the parent has the property set at a higher specificity.
bool	hasValue () const

Public Attributes
std::string_view	name
	Property name, such as "color".
std::optional< T >	value
	Property value, or std::nullopt if not set.
PropertyState	state = PropertyState::NotSet
	Current state of the property, such as set or inherited.
css::Specificity	specificity
	Specificity of the property, used for inheritance.
GetInitialFn< T >	getInitialFn
	Function which is called to get the initial value of the property.

Detailed Description

template<typename T, PropertyCascade kCascade = PropertyCascade::None>
struct donner::svg::Property< T, kCascade >

Holds a CSS property, which has a name and value, and integrates with inheritance to allow cascading values using the CSS model with specificity.

Template Parameters

T	The type of the property value.
kCascade	Determines how this property type participates in the cascade, to allow for specific property types to be excluded from inheritance.

Constructor & Destructor Documentation

Property()

template<typename T, PropertyCascade kCascade = PropertyCascade::None>

donner::svg::Property< T, kCascade >::Property ( std::string_view name, GetInitialFn< T > getInitialFn = []() -> std::optional<T> { return std::nullopt; } )

inline

Property constructor, which is initially unset.

Parameters

name	Name of the property, such as "color".
getInitialFn	Function to get the initial value of the property.

Member Function Documentation

get()

template<typename T, PropertyCascade kCascade = PropertyCascade::None>

std::optional< T > donner::svg::Property< T, kCascade >::get ( ) const

inline

Get the property value, without considering inheritance.

Returns the initial value if the property has not been set.

Returns

The value if it is set, or the initial value if it is not. Returns std::nullopt if the property is none.

getRequired()

template<typename T, PropertyCascade kCascade = PropertyCascade::None>

T donner::svg::Property< T, kCascade >::getRequired ( ) const

inline

Gets the value of the property, requiring that the value is not std::nullopt.

Returns

The value.

getRequiredRef()

template<typename T, PropertyCascade kCascade = PropertyCascade::None>

const T & donner::svg::Property< T, kCascade >::getRequiredRef ( ) const

inline

Gets a const-ref to the value, for accessing complex types without copying.

Requires that hasValue() is true.

Returns

const T& Reference to the value.

hasValue()

template<typename T, PropertyCascade kCascade = PropertyCascade::None>

bool donner::svg::Property< T, kCascade >::hasValue ( ) const

inline

Returns

true if the property has any value set, including CSS built-in values.

inheritFrom()

template<typename T, PropertyCascade kCascade = PropertyCascade::None>

Property< T, kCascade > donner::svg::Property< T, kCascade >::inheritFrom ( const Property< T, kCascade > & parent, PropertyInheritOptions options = PropertyInheritOptions::All ) const

inlinenodiscard

Inherit the property from the parent element, if the parent has the property set at a higher specificity.

Note that this typically inherits "backwards", taking a local property which may already have a value and then overriding it if the parent has a more specific one. This is not required, but doing so is more efficient since we don't need to keep setting the property as the child overrides each parent.

Parameters

parent	Parent property to inherit into this one.
options	Options to control how inheritance is performed, to conditionally disable inheritance.

Returns

Property with the resolved value after inheritance.

set() [1/2]

template<typename T, PropertyCascade kCascade = PropertyCascade::None>

void donner::svg::Property< T, kCascade >::set ( PropertyState newState, css::Specificity newSpecificity )

inline

Unset the current value and set the property to a specific state.

Parameters

newState	New state to set.
newSpecificity	Specificity to use.

set() [2/2]

template<typename T, PropertyCascade kCascade = PropertyCascade::None>

void donner::svg::Property< T, kCascade >::set ( std::optional< T > newValue, css::Specificity newSpecificity )

inline

Set the property to a new value at the given specificity.

Parameters

newValue	Value to set, or std::nullopt to set to an empty value.
newSpecificity	Specificity to use.

substitute()

template<typename T, PropertyCascade kCascade = PropertyCascade::None>

void donner::svg::Property< T, kCascade >::substitute ( std::optional< T > newValue )

inline

Replace the current property's value with a new value at the current specificity.

Parameters

newValue

Value to use to replace the existing one.

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

• donner/svg/properties/Property.h