pdk_classy/extract/
from_context_once.rs

1// Copyright 2023 Salesforce, Inc. All rights reserved.
2use std::{
3    future::{ready, Future, Ready},
4    ops::Deref,
5};
6
7use super::FromContext;
8use crate::BoxError;
9
10mod mode {
11    pub enum Once {}
12
13    pub enum Repeat {}
14}
15
16pub struct Exclusive<'c, C> {
17    context: &'c C,
18}
19
20impl<'c, C> Exclusive<'c, C> {
21    pub(crate) fn new(context: &'c C) -> Self {
22        Self { context }
23    }
24
25    pub fn get(&self) -> &'c C {
26        self.context
27    }
28}
29
30impl<C> Deref for Exclusive<'_, C> {
31    type Target = C;
32
33    fn deref(&self) -> &Self::Target {
34        self.get()
35    }
36}
37
38pub trait FromContextOnce<C, M = mode::Once>: Sized {
39    type Error: Into<BoxError>;
40
41    type Future<'c>: Future<Output = Result<Self, Self::Error>> + 'c
42    where
43        C: 'c;
44
45    fn from_context_once(context: Exclusive<C>) -> Self::Future<'_>;
46}
47
48impl<C, T> FromContextOnce<C, mode::Repeat> for T
49where
50    for<'c> T: FromContext<C> + 'c,
51{
52    type Error = T::Error;
53
54    type Future<'c>
55        = Ready<Result<Self, Self::Error>>
56    where
57        C: 'c,
58        Self: 'c;
59
60    fn from_context_once(context: Exclusive<C>) -> Self::Future<'_> {
61        ready(T::from_context(&context))
62    }
63}
pdk_classy/extract/from_context_once.rs

pdk_classy/extract/
from_context_once.rs
