pub enum Callback2<IN, OUT> {
    Callback2(Rc<dyn Fn(IN) -> OUT>),
    Callback2Once(Rc<RefCell<Option<Box<dyn FnOnce(IN) -> OUT>>>>),
}
Expand description

Universal closure wrapper.

An `Rc` wrapper is used to make it cloneable.

Variants

Callback2(Rc<dyn Fn(IN) -> OUT>)

A closure which can be called multiple times

Callback2Once(Rc<RefCell<Option<Box<dyn FnOnce(IN) -> OUT>>>>)

A closure which can only be called once. The closure will panic if it is called more than once.

Implementations

This method calls the closure’s function.

Creates a closure from an FnOnce. The programmer is responsible for ensuring that the closure is only called once. If it is called more than once, the closure will panic.

Creates a “no-op” closure which can be used when it is not suitable to use an Option<Lambda>.

Changes the input & output types of the closure to others. Works like the map method but in the opposite direction.

Trait Implementations

Returns a copy of the value. Read more
Performs copy-assignment from source. Read more
Formats the value using the given formatter. Read more
Returns the “default value” for a type. Read more
Converts to this type from the input type.
This method tests for self and other values to be equal, and is used by ==. Read more
This method tests for !=. The default implementation is almost always sufficient, and should not be overridden without very good reason. Read more

Auto Trait Implementations

Blanket Implementations

Gets the TypeId of self. Read more
Immutably borrows from an owned value. Read more
Mutably borrows from an owned value. Read more

Returns the argument unchanged.

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

Convert self to a value of a Properties struct.
Convert self to a value of a Properties struct.
The resulting type after obtaining ownership.
Creates owned data from borrowed data, usually by cloning. Read more
Uses borrowed data to replace owned data, usually by cloning. Read more
The type returned in the event of a conversion error.
Performs the conversion.
The type returned in the event of a conversion error.
Performs the conversion.