1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
|
//! Run asynchronous actions.
mod action;
pub use action::Action;
use crate::core::widget;
use crate::futures::MaybeSend;
use std::fmt;
use std::future::Future;
/// A set of asynchronous actions to be performed by some runtime.
#[must_use = "`Command` must be returned to runtime to take effect"]
pub struct Command<T>(Internal<Action<T>>);
#[derive(Debug)]
enum Internal<T> {
None,
Single(T),
Batch(Vec<T>),
}
impl<T> Command<T> {
/// Creates an empty [`Command`].
///
/// In other words, a [`Command`] that does nothing.
pub const fn none() -> Self {
Self(Internal::None)
}
/// Creates a [`Command`] that performs a single [`Action`].
pub const fn single(action: Action<T>) -> Self {
Self(Internal::Single(action))
}
/// Creates a [`Command`] that performs a [`widget::Operation`].
pub fn widget(operation: impl widget::Operation<T> + 'static) -> Self {
Self::single(Action::Widget(Box::new(operation)))
}
/// Creates a [`Command`] that performs the action of the given future.
pub fn perform<A>(
future: impl Future<Output = T> + 'static + MaybeSend,
f: impl FnOnce(T) -> A + 'static + MaybeSend,
) -> Command<A> {
use iced_futures::futures::FutureExt;
Command::single(Action::Future(Box::pin(future.map(f))))
}
/// Creates a [`Command`] that performs the actions of all the given
/// commands.
///
/// Once this command is run, all the commands will be executed at once.
pub fn batch(commands: impl IntoIterator<Item = Command<T>>) -> Self {
let mut batch = Vec::new();
for Command(command) in commands {
match command {
Internal::None => {}
Internal::Single(command) => batch.push(command),
Internal::Batch(commands) => batch.extend(commands),
}
}
Self(Internal::Batch(batch))
}
/// Applies a transformation to the result of a [`Command`].
pub fn map<A>(
self,
f: impl Fn(T) -> A + 'static + MaybeSend + Sync + Clone,
) -> Command<A>
where
T: 'static,
A: 'static,
{
match self.0 {
Internal::None => Command::none(),
Internal::Single(action) => Command::single(action.map(f)),
Internal::Batch(batch) => Command(Internal::Batch(
batch
.into_iter()
.map(|action| action.map(f.clone()))
.collect(),
)),
}
}
/// Returns all of the actions of the [`Command`].
pub fn actions(self) -> Vec<Action<T>> {
let Command(command) = self;
match command {
Internal::None => Vec::new(),
Internal::Single(action) => vec![action],
Internal::Batch(batch) => batch,
}
}
}
impl<T> fmt::Debug for Command<T> {
fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
let Command(command) = self;
command.fmt(f)
}
}
|