Struct MarkupDelegate 

pub struct MarkupDelegate { /* private fields */ }

An untyped callback (the equivalent of a delegate instance): what an event subscription declared in metadata receives as its handler, and what a binding to a method produces.

Implementations

impl MarkupDelegate

pub fn new(f: impl Fn(&[MarkupValue]) -> MarkupValue + 'static) -> Self

pub fn for_method( target: MarkupValue, declaring_type: &'static MarkupType, method: &'static MarkupMethod, ) -> Self

The delegate of a method declared in metadata, bound to target (method.CreateDelegate(type, target) in the managed original). target is the instance for an instance method and ignored for a static one; declaring_type is the type whose metadata lists method. The delegate keeps the target alive.

invoke calls the method with the arguments given (after the instance) and discards a failure; try_invoke reports it.

pub fn for_method_of_source( target: &BoxedValue, declaring_type: &'static MarkupType, method: &'static MarkupMethod, ) -> Self

The delegate of a method of a binding source: what a binding to a method reads. As for_method, but the delegate does not keep target alive (a source that is a reference; a plain value is held as a binding holds it, by value). Once the target is gone target is None, is_target_alive is false and invoking the delegate does nothing.

Deviation (DEVIATIONS.md, Bindings): the managed delegate has its target strongly, and so has the command made from it. A template that binds a command of one of its parts to a method of the templated control is a cycle there (the control, its template, the part, the value of its command property, the control), which the collector frees; without one it would never be freed.

pub fn invoke(&self, arguments: &[MarkupValue]) -> MarkupValue

Calls the callback.

pub fn try_invoke( &self, arguments: &[MarkupValue], ) -> Result<MarkupValue, MarkupInvokeError>

Calls the callback. For the delegate of a declared method (for_method) a failure of the call (wrong arguments, a failing member) is returned.

pub fn target(&self) -> MarkupValue

The instance the delegate of a declared instance method is bound to (the Target of the managed original). None for a static method and for a delegate that was not created from a declared method.

pub fn is_target_alive(&self) -> bool

Whether the delegate can still call what it was created for: false once the target of the delegate of a binding source (for_method_of_source) is gone.

pub fn method(&self) -> Option<&'static MarkupMethod>

The declared method the delegate was created from (the Method of the managed original), if it was created with for_method.

pub fn declaring_type(&self) -> Option<&'static MarkupType>

The type whose metadata declares method.

Trait Implementations

impl Clone for MarkupDelegate

fn clone(&self) -> Self

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl Debug for MarkupDelegate

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

Formats the value using the given formatter.

impl Display for MarkupDelegate

The name of the delegate type, as the managed original prints a delegate (System.Action, System.Action`1[System.Int32], System.Func`2[System.Object,System.Boolean]) for the delegate of a declared method; System.Delegate otherwise.

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

Formats the value using the given formatter.

impl PartialEq for MarkupDelegate

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

Equality operator ==.

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

Inequality operator !=.