Enum pango::Direction

#[non_exhaustive]
pub enum Direction {
    Ltr,
    Rtl,
    TtbLtr,
    TtbRtl,
    WeakLtr,
    WeakRtl,
    Neutral,
}

Direction represents a direction in the Unicode bidirectional algorithm.

Not every value in this enumeration makes sense for every usage of Direction; for example, the return value of unichar_direction() and find_base_dir() cannot be PANGO_DIRECTION_WEAK_LTR or PANGO_DIRECTION_WEAK_RTL, since every character is either neutral or has a strong direction; on the other hand PANGO_DIRECTION_NEUTRAL doesn’t make sense to pass to itemize_with_base_dir().

The PANGO_DIRECTION_TTB_LTR, PANGO_DIRECTION_TTB_RTL values come from an earlier interpretation of this enumeration as the writing direction of a block of text and are no longer used. See Gravity for how vertical text is handled in Pango.

If you are interested in text direction, you should really use fribidi directly. Direction is only retained because it is used in some public apis.

Variants (Non-exhaustive)

Non-exhaustive enums could have additional variants added in future. Therefore, when matching against variants of non-exhaustive enums, an extra wildcard arm must be added to account for any future variants.

Ltr

A strong left-to-right direction

Rtl

A strong right-to-left direction

TtbLtr

Deprecated value; treated the same as PANGO_DIRECTION_RTL.

TtbRtl

Deprecated value; treated the same as PANGO_DIRECTION_LTR

WeakLtr

A weak left-to-right direction

WeakRtl

A weak right-to-left direction

Neutral

No direction specified

Trait Implementations

impl Clone for Direction

fn clone(&self) -> Direction

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for Direction

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

Formats the value using the given formatter.

impl From<Direction> for Value

fn from(v: Direction) -> Self

Converts to this type from the input type.

impl<'a> FromValue<'a> for Direction

type Checker = GenericValueTypeChecker<Direction>

Value type checker.

unsafe fn from_value(value: &'a Value) -> Self

Get the contained value from a Value.

impl HasParamSpec for Direction

type ParamSpec = ParamSpecEnum

type SetValue = Direction

Preferred value to be used as setter for the associated ParamSpec.

type BuilderFn = fn(_: &str, _: Direction) -> ParamSpecEnumBuilder<'_, Direction>

fn param_spec_builder() -> Self::BuilderFn

impl Hash for Direction

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for Direction

fn cmp(&self, other: &Direction) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized + PartialOrd,

Restrict a value to a certain interval.

impl PartialEq for Direction

fn eq(&self, other: &Direction) -> bool

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

fn ne(&self, other: &Rhs) -> bool

This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason.

impl PartialOrd for Direction

fn partial_cmp(&self, other: &Direction) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

This method tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

This method tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

This method tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

This method tests greater than or equal to (for self and other) and is used by the >= operator.

impl StaticType for Direction

fn static_type() -> Type

Returns the type identifier of Self.

impl ToValue for Direction

fn to_value(&self) -> Value

Convert a value to a Value.

fn value_type(&self) -> Type

Returns the type identifier of self.

impl ValueType for Direction

type Type = Direction

Type to get the Type from.

impl Copy for Direction

impl Eq for Direction

impl StructuralPartialEq for Direction