#[repr(transparent)]pub struct Value { /* private fields */ }
Expand description
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. An opaque structure used to hold different types of values.
The data within the structure has protected scope: it is accessible only
to functions within a GTypeValueTable
structure, or implementations of
the g_value_*() API. That is, code portions which implement new fundamental
types.
Value
users cannot make any assumptions about how data is stored
within the 2 element data
union, and the g_type
member should
only be accessed through the G_VALUE_TYPE() macro.
Implementations§
source§impl Value
impl Value
sourcepub fn for_value_type<T: ValueType>() -> Self
pub fn for_value_type<T: ValueType>() -> Self
Creates a new Value
that is initialized for a given ValueType
.
sourcepub fn get<'a, T>(
&'a self
) -> Result<T, <<T as FromValue<'_>>::Checker as ValueTypeChecker>::Error>where
T: FromValue<'a>,
pub fn get<'a, T>( &'a self ) -> Result<T, <<T as FromValue<'_>>::Checker as ValueTypeChecker>::Error>where T: FromValue<'a>,
Tries to get a value of type T
.
Returns Ok
if the type is correct.
sourcepub fn get_owned<T>(
&self
) -> Result<T, <<T as FromValue<'_>>::Checker as ValueTypeChecker>::Error>where
T: for<'b> FromValue<'b> + 'static,
pub fn get_owned<T>( &self ) -> Result<T, <<T as FromValue<'_>>::Checker as ValueTypeChecker>::Error>where T: for<'b> FromValue<'b> + 'static,
Tries to get a value of an owned type T
.
sourcepub fn is<T: StaticType>(&self) -> bool
pub fn is<T: StaticType>(&self) -> bool
Returns true
if the type of the value corresponds to T
or is a sub-type of T
.
sourcepub fn is_type(&self, type_: Type) -> bool
pub fn is_type(&self, type_: Type) -> bool
Returns true
if the type of the value corresponds to type_
or is a sub-type of type_
.
sourcepub fn type_transformable(src: Type, dst: Type) -> bool
pub fn type_transformable(src: Type, dst: Type) -> bool
Returns whether Value
s of type src
can be transformed to type dst
.
sourcepub fn transform<T: ValueType>(&self) -> Result<Value, BoolError>
pub fn transform<T: ValueType>(&self) -> Result<Value, BoolError>
Tries to transform the value into a value of the target type
sourcepub fn transform_with_type(&self, type_: Type) -> Result<Value, BoolError>
pub fn transform_with_type(&self, type_: Type) -> Result<Value, BoolError>
Tries to transform the value into a value of the target type
pub fn try_into_send_value<T: Send + StaticType>( self ) -> Result<SendValue, Self>
Trait Implementations§
source§impl<'a> FromValue<'a> for &'a Value
impl<'a> FromValue<'a> for &'a Value
§type Checker = NopChecker
type Checker = NopChecker
source§unsafe fn from_value(value: &'a Value) -> Self
unsafe fn from_value(value: &'a Value) -> Self
Value
. Read moresource§impl<'a> FromValue<'a> for Value
impl<'a> FromValue<'a> for Value
§type Checker = NopChecker
type Checker = NopChecker
source§unsafe fn from_value(value: &'a Value) -> Self
unsafe fn from_value(value: &'a Value) -> Self
Value
. Read more