Enum Handler 

pub enum Handler<M> {
    Plain(M),
    Bool(fn(bool) -> M),
    Index(fn(usize) -> M),
    Number(fn(f32) -> M),
}

A message a form named, in the shape the widget holding it needs.

Widgets do not all take a message the same way, and none of them takes a closure: a Button holds an M, a Checkbox a fn(bool) -> M, a List a fn(usize) -> M, a Slider a fn(f32) -> M. Those are function pointers, so nothing this crate could build from a name would fit — but an enum’s tuple variant already is one:

#[derive(Clone, Copy)]
enum Message {
    Save,
    Notify(bool),
}

let save = Handler::Plain(Message::Save);
// `Message::Notify` *is* a `fn(bool) -> Message`.
let notify = Handler::Bool(Message::Notify);

Variants

Plain(M)

The message itself, for a widget that holds one: a button, a select, a text field’s submit.

Bool(fn(bool) -> M)

fn(bool) -> M — a checkbox, a toggle, a collapse.

Index(fn(usize) -> M)

fn(usize) -> M — anything that selects one of several.

Number(fn(f32) -> M)

fn(f32) -> M — a slider, a rating.

Trait Implementations

impl<M: Clone> Clone for Handler<M>

fn clone(&self) -> Handler<M>

Returns a duplicate of the value.

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

Performs copy-assignment from source.

impl<M: Copy> Copy for Handler<M>

impl<M: Debug> Debug for Handler<M>

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

Formats the value using the given formatter.