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
109
110
111
112
113
//! Thread-safe combining of two by-ref contexts, keeping the first value, with [`send_ref_apply_first`].
//!
//! This is the thread-safe counterpart of [`RefApplyFirst`](crate::classes::RefApplyFirst).
//!
//! ### Examples
//!
//! ```
//! use fp_library::{
//! brands::*,
//! functions::*,
//! types::*,
//! };
//!
//! let x = ArcLazy::new(|| 3);
//! let y = ArcLazy::new(|| 4);
//! let result = send_ref_apply_first::<LazyBrand<ArcLazyConfig>, _, _>(&x, &y);
//! assert_eq!(*result.evaluate(), 3);
//! ```
#[fp_macros::document_module]
mod inner {
use {
crate::kinds::*,
fp_macros::*,
};
/// A type class for combining two thread-safe by-ref contexts, keeping the first value.
///
/// Requires `A: Clone + Send + Sync` because the closure receives `&A` and must produce
/// an owned `A`. The default implementation uses [`SendRefLift::send_ref_lift2`](crate::classes::SendRefLift::send_ref_lift2).
#[kind(type Of<'a, A: 'a>: 'a;)]
pub trait SendRefApplyFirst: crate::classes::SendRefLift {
/// Combines two contexts, keeping the value from the first.
#[document_signature]
///
#[document_type_parameters(
"The lifetime of the values.",
"The type of the value in the first context. Must be `Clone + Send + Sync`.",
"The type of the value in the second context."
)]
///
#[document_parameters("The first context.", "The second context.")]
///
#[document_returns("A new context containing the value from the first context.")]
#[document_examples]
///
/// ```
/// use fp_library::{
/// brands::*,
/// classes::*,
/// types::*,
/// };
///
/// let x = ArcLazy::new(|| 3);
/// let y = ArcLazy::new(|| 4);
/// let result = LazyBrand::<ArcLazyConfig>::send_ref_apply_first(&x, &y);
/// assert_eq!(*result.evaluate(), 3);
/// ```
fn send_ref_apply_first<'a, A: Clone + Send + Sync + 'a, B: Send + Sync + 'a>(
fa: &Apply!(<Self as Kind!( type Of<'a, T: 'a>: 'a; )>::Of<'a, A>),
fb: &Apply!(<Self as Kind!( type Of<'a, T: 'a>: 'a; )>::Of<'a, B>),
) -> Apply!(<Self as Kind!( type Of<'a, T: 'a>: 'a; )>::Of<'a, A>) {
Self::send_ref_lift2(|a: &A, _: &B| a.clone(), fa, fb)
}
}
/// Blanket implementation of [`SendRefApplyFirst`].
#[document_type_parameters("The brand type.")]
impl<Brand: crate::classes::SendRefLift> SendRefApplyFirst for Brand {}
/// Combines two thread-safe contexts, keeping the value from the first.
///
/// Free function version that dispatches to [the type class' associated function][`SendRefApplyFirst::send_ref_apply_first`].
#[document_signature]
///
#[document_type_parameters(
"The lifetime of the values.",
"The brand of the context.",
"The type of the value in the first context. Must be `Clone + Send + Sync`.",
"The type of the value in the second context."
)]
///
#[document_parameters("The first context.", "The second context.")]
///
#[document_returns("A new context containing the value from the first context.")]
#[document_examples]
///
/// ```
/// use fp_library::{
/// brands::*,
/// functions::*,
/// types::*,
/// };
///
/// let x = ArcLazy::new(|| 3);
/// let y = ArcLazy::new(|| 4);
/// let result = send_ref_apply_first::<LazyBrand<ArcLazyConfig>, _, _>(&x, &y);
/// assert_eq!(*result.evaluate(), 3);
/// ```
pub fn send_ref_apply_first<
'a,
Brand: SendRefApplyFirst,
A: Clone + Send + Sync + 'a,
B: Send + Sync + 'a,
>(
fa: &Apply!(<Brand as Kind!( type Of<'a, T: 'a>: 'a; )>::Of<'a, A>),
fb: &Apply!(<Brand as Kind!( type Of<'a, T: 'a>: 'a; )>::Of<'a, B>),
) -> Apply!(<Brand as Kind!( type Of<'a, T: 'a>: 'a; )>::Of<'a, A>) {
Brand::send_ref_apply_first(fa, fb)
}
}
pub use inner::*;