teloxide_core_ng/requests/
has_payload.rs

1use either::Either;
2
3use crate::requests::Payload;
4
5/// Represents types having payload inside.
6///
7/// This trait is something between [`DerefMut`] and [`BorrowMut`] — it allows
8/// only one implementation per type (the [output type] is associated, not
9/// generic), has implementations for all types `P` such `P: `[`Payload`], but
10/// has no magic compiler support like [`DerefMut`] does nor does it require
11/// any laws about `Eq`, `Ord` and `Hash` as [`BorrowMut`] does.
12///
13/// Also the [output type] is bounded by the [`Payload`] trait.
14///
15/// This trait is mostly used to implement payload setters (on both payloads &
16/// requests), so you probably won't find yourself using it directly.
17///
18/// [`DerefMut`]: std::ops::DerefMut
19/// [`BorrowMut`]: std::borrow::BorrowMut
20/// [`Payload`]: crate::requests::Payload
21/// [output type]: HasPayload::Payload
22pub trait HasPayload {
23    /// The type of the payload contained.
24    type Payload: Payload;
25
26    /// Gain mutable access to the underlying payload.
27    fn payload_mut(&mut self) -> &mut Self::Payload;
28
29    /// Gain immutable access to the underlying payload.
30    fn payload_ref(&self) -> &Self::Payload;
31
32    /// Update payload with a function
33    fn with_payload_mut<F>(mut self, f: F) -> Self
34    where
35        Self: Sized,
36        F: FnOnce(&mut Self::Payload),
37    {
38        f(self.payload_mut());
39        self
40    }
41}
42
43impl<P> HasPayload for P
44where
45    P: Payload,
46{
47    type Payload = Self;
48
49    fn payload_mut(&mut self) -> &mut Self::Payload {
50        self
51    }
52
53    fn payload_ref(&self) -> &Self::Payload {
54        self
55    }
56}
57
58impl<L, R> HasPayload for Either<L, R>
59where
60    L: HasPayload,
61    R: HasPayload<Payload = L::Payload>,
62{
63    type Payload = L::Payload;
64
65    fn payload_mut(&mut self) -> &mut Self::Payload {
66        self.as_mut().either(<_>::payload_mut, <_>::payload_mut)
67    }
68
69    fn payload_ref(&self) -> &Self::Payload {
70        self.as_ref().either(<_>::payload_ref, <_>::payload_ref)
71    }
72}
teloxide_core_ng/requests/has_payload.rs

teloxide_core_ng/requests/
has_payload.rs
