Enum gstreamer::TagMergeMode

#[non_exhaustive]
pub enum TagMergeMode {
    Undefined,
    ReplaceAll,
    Replace,
    Append,
    Prepend,
    Keep,
    KeepAll,
    Count,
    // some variants omitted
}

The different tag merging modes are basically replace, overwrite and append, but they can be seen from two directions. Given two taglists: (A) the tags already in the element and (B) the ones that are supplied to the element ( e.g. via TagSetterExt::merge_tags() / gst_tag_setter_add_tags() or a EventType::Tag), how are these tags merged? In the table below this is shown for the cases that a tag exists in the list (A) or does not exists (!A) and combinations thereof.

merge mode	A + B	A + !B	!A + B	!A + !B
REPLACE_ALL	B	ø	B	ø
REPLACE	B	A	B	ø
APPEND	A, B	A	B	ø
PREPEND	B, A	A	B	ø
KEEP	A	A	B	ø
KEEP_ALL	A	A	ø	ø

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.

Undefined

undefined merge mode

ReplaceAll

replace all tags (clear list and append)

Replace

replace tags

Append

append tags

Prepend

prepend tags

Keep

keep existing tags

KeepAll

keep all existing tags

Count

the number of merge modes

Trait Implementations

impl Clone for TagMergeMode

fn clone(&self) -> TagMergeMode

Returns a copy of the value.

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

Performs copy-assignment from source.

impl Debug for TagMergeMode

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

Formats the value using the given formatter.

impl<'a> FromValue<'a> for TagMergeMode

type Checker = GenericValueTypeChecker<Self>

Value type checker.

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

Get the contained value from a Value.

impl Hash for TagMergeMode

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, 

Feeds a slice of this type into the given Hasher.

impl Ord for TagMergeMode

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

This method returns an Ordering between self and other.

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

Compares and returns the maximum of two values.

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

Compares and returns the minimum of two values.

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

Restrict a value to a certain interval.

impl PartialEq<TagMergeMode> for TagMergeMode

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

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

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

This method tests for !=.

impl PartialOrd<TagMergeMode> for TagMergeMode

fn partial_cmp(&self, other: &TagMergeMode) -> 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 TagMergeMode

fn static_type() -> Type

Returns the type identifier of Self.

impl ToValue for TagMergeMode

fn to_value(&self) -> Value

Convert a value to a Value.

fn value_type(&self) -> Type

Returns the type identifer of self.

impl ValueType for TagMergeMode

type Type = Self

Type to get the Type from.

impl Copy for TagMergeMode

impl Eq for TagMergeMode

impl StructuralEq for TagMergeMode

impl StructuralPartialEq for TagMergeMode