Struct gstreamer_base::Value

#[repr(C)]
pub struct Value(_, _);

A generic value capable of carrying various types.

Once created the type of the value can't be changed.

Some types (e.g. String and objects) support None values while others (e.g. numeric types) don't.

Value does not implement the Send trait, but SendValue can be used instead.

See the module documentation for more details.

Methods

impl Value

pub fn from_type(type_: Type) -> Value

Creates a new Value that is initialized with type_

pub fn downcast<'a, T>(self) -> Result<TypedValue<T>, Value> where
    T: FromValueOptional<'a> + SetValue, 

Tries to downcast to a TypedValue.

Returns Ok(TypedValue<T>) if the value carries a type corresponding to T and Err(self) otherwise.

pub fn downcast_ref<'a, T>(&self) -> Option<&TypedValue<T>> where
    T: FromValueOptional<'a> + SetValue, 

Tries to downcast to a &TypedValue.

Returns Some(&TypedValue<T>) if the value carries a type corresponding to T and None otherwise.

pub fn get<'a, T>(&'a self) -> Option<T> where
    T: FromValueOptional<'a>, 

Tries to get a value of type T.

Returns Some if the type is correct and the value is not None.

This function doesn't distinguish between type mismatches and correctly typed None values. Use downcast or is for that.

pub fn is<'a, T>(&self) -> bool where
    T: FromValueOptional<'a> + SetValue, 

Returns true if the type of the value corresponds to T or is a sub-type of T.

pub fn type_(&self) -> Type

Returns the type of the value.

pub fn type_transformable(src: Type, dst: Type) -> bool

Returns whether Values of type src can be transformed to type dst.

pub fn try_into_send_value<'a, T>(self) -> Result<SendValue, Value> where
    T: FromValueOptional<'a> + SetValue + Send, 

Trait Implementations

impl GstValueExt for Value

fn can_compare(&self, other: &Value) -> bool

fn compare(&self, other: &Value) -> Option<Ordering>

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

fn can_intersect(&self, other: &Value) -> bool

fn intersect(&self, other: &Value) -> Option<Value>

fn can_subtract(&self, other: &Value) -> bool

fn subtract(&self, other: &Value) -> Option<Value>

fn can_union(&self, other: &Value) -> bool

fn union(&self, other: &Value) -> Option<Value>

fn fixate(&self) -> Option<Value>

fn is_fixed(&self) -> bool

fn is_subset(&self, superset: &Value) -> bool

fn serialize(&self) -> Option<String>

fn deserialize<'a, T>(s: T) -> Option<Value> where
    T: Into<&'a str>, 

impl ToValue for Value

fn to_value(&self) -> Value

Returns a Value clone of self.

fn to_value_type(&self) -> Type

Returns the type identifer of self.

impl FromGlibPtrNone<*const GValue> for Value

unsafe fn from_glib_none(ptr: *const GValue) -> Value

impl FromGlibPtrNone<*mut GValue> for Value

unsafe fn from_glib_none(ptr: *mut GValue) -> Value

impl Drop for Value

fn drop(&mut self)

Executes the destructor for this type.

impl<'a> ToGlibContainerFromSlice<'a, *mut GValue> for &'a Value

type Storage = &'a [&'a Value]

fn to_glib_none_from_slice(t: &'a [&'a Value]) -> (*mut GValue, &'a [&'a Value])

fn to_glib_container_from_slice(
    t: &'a [&'a Value]
) -> (*mut GValue, &'a [&'a Value])

fn to_glib_full_from_slice(t: &[&'a Value]) -> *mut GValue

impl<'a> ToGlibContainerFromSlice<'a, *const GValue> for &'a Value

type Storage = &'a [&'a Value]

fn to_glib_none_from_slice(
    t: &'a [&'a Value]
) -> (*const GValue, &'a [&'a Value])

fn to_glib_container_from_slice(
    &'a [&'a Value]
) -> (*const GValue, &'a [&'a Value])

fn to_glib_full_from_slice(&[&'a Value]) -> *const GValue

impl FromGlibContainerAsVec<*mut GValue, *const *mut GValue> for Value

unsafe fn from_glib_none_num_as_vec(
    ptr: *const *mut GValue,
    num: usize
) -> Vec<Value>

unsafe fn from_glib_container_num_as_vec(
    *const *mut GValue,
    usize
) -> Vec<Value>

unsafe fn from_glib_full_num_as_vec(*const *mut GValue, usize) -> Vec<Value>

impl FromGlibContainerAsVec<*mut GValue, *mut *mut GValue> for Value

unsafe fn from_glib_none_num_as_vec(
    ptr: *mut *mut GValue,
    num: usize
) -> Vec<Value>

unsafe fn from_glib_container_num_as_vec(
    ptr: *mut *mut GValue,
    num: usize
) -> Vec<Value>

unsafe fn from_glib_full_num_as_vec(
    ptr: *mut *mut GValue,
    num: usize
) -> Vec<Value>

impl Clone for Value

fn clone(&self) -> Value

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<'a> ToGlibPtrMut<'a, *mut GValue> for Value

type Storage = &'a mut Value

fn to_glib_none_mut(&'a mut self) -> StashMut<'a, *mut GValue, Value>

Transfer: none.

impl Uninitialized for Value

unsafe fn uninitialized() -> Value

Returns an uninitialized value.

impl Debug for Value

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

Formats the value using the given formatter.

impl FromGlibPtrFull<*mut GValue> for Value

unsafe fn from_glib_full(ptr: *mut GValue) -> Value

impl FromGlibPtrArrayContainerAsVec<*mut GValue, *mut *mut GValue> for Value

unsafe fn from_glib_none_as_vec(ptr: *mut *mut GValue) -> Vec<Value>

unsafe fn from_glib_container_as_vec(ptr: *mut *mut GValue) -> Vec<Value>

unsafe fn from_glib_full_as_vec(ptr: *mut *mut GValue) -> Vec<Value>

impl FromGlibPtrArrayContainerAsVec<*mut GValue, *const *mut GValue> for Value

unsafe fn from_glib_none_as_vec(ptr: *const *mut GValue) -> Vec<Value>

unsafe fn from_glib_container_as_vec(*const *mut GValue) -> Vec<Value>

unsafe fn from_glib_full_as_vec(*const *mut GValue) -> Vec<Value>

impl<'a> ToGlibPtr<'a, *const GValue> for Value

type Storage = &'a Value

fn to_glib_none(&'a self) -> Stash<'a, *const GValue, Value>

Transfer: none.

fn to_glib_container(&'a self) -> Stash<'a, P, Self>

Transfer: container.

fn to_glib_full(&self) -> P

Transfer: full.

impl From<SendValue> for Value

fn from(value: SendValue) -> Value

Performs the conversion.

impl<'a, T> From<&'a T> for Value where
    T: SetValue + ?Sized, 

fn from(value: &'a T) -> Value

Performs the conversion.

impl<'a, T> From<Option<&'a T>> for Value where
    T: SetValueOptional + ?Sized, 

fn from(value: Option<&'a T>) -> Value

Performs the conversion.

impl<T> From<TypedValue<T>> for Value

fn from(value: TypedValue<T>) -> Value

Performs the conversion.