Struct zng::var::TraceValueArgs

pub struct TraceValueArgs<'a, T>
where
    T: VarValue,
{ /* private fields */ }

Args for Var::trace_value.

Implementations

impl<'a, T> TraceValueArgs<'a, T>

where T: VarValue,

pub fn value(&self) -> &'a T

Strongly-typed reference to the new value.

Methods from Deref<Target = AnyVarHookArgs<'a>>

pub fn value(&self) -> &'a (dyn AnyVarValue + 'static)

Reference the updated value.

pub fn update(&self) -> bool

If update was explicitly requested.

Note that bindings/mappings propagate this update request.

pub fn value_type(&self) -> TypeId

Value type ID.

pub fn tags(&self) -> &[Box<dyn AnyVarValue>]

Custom tag objects.

pub fn tags_vec(&self) -> Vec<Box<dyn AnyVarValue>>

Clone the custom tag objects set by the code that updated the value.

pub fn downcast_value<T>(&self) -> Option<&T>

where T: VarValue,

Reference the value, if it is of type T.

pub fn downcast_tags<T>(&self) -> impl Iterator<Item = &T>

where T: VarValue,

Reference all custom tag values of type T.

pub fn as_strong<T>(&self) -> Option<VarHookArgs<'_, T>>

where T: VarValue,

Try cast to strongly typed args.

Trait Implementations

impl<'a, T> Deref for TraceValueArgs<'a, T>

where T: VarValue,

type Target = AnyVarHookArgs<'a>

The resulting type after dereferencing.

fn deref(&self) -> &<TraceValueArgs<'a, T> as Deref>::Target

Dereferences the value.