trellis-runner 0.2.2

Calculation runner
Documentation 
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

use crate::CancellationGuard;

use std::ops::Deref;

/// Trait implemented by all problems solvable by `Trellis`
///
/// A procedure defines the core loop of the solver. Typically we would write a for loop,
/// consisting of an initialisation step where the procedure is arranged, a procedure carried out
/// on each loop iteration, and a finalisation step prior to return. This trait separates these
/// methods so they can be called by the [`Runner`]
pub trait Procedure<P> {
    /// The type returned to the caller.
    ///
    /// Trellis defines a data-rich [`Output`], which can be constructed from the procedure, and
    /// internal state. In some circumstances it may be appropriate to return this type to the
    /// caller. In other circumstances it may be preferential to bury this complexity, returning
    /// the caller a custom datatype.
    type Output;

    type State;

    /// An identifier for the procedure.
    ///
    /// This identifier is printed in tracing logs
    const NAME: &'static str;
    /// Initialisation.
    ///
    /// This step prepares the state object for the main procedure loop.
    fn initialise(&self, _problem: &mut P, _state: &mut Self::State) {}
    /// One iteration of the core algorithm
    fn step(&self, problem: &mut P, state: &mut Self::State, guard: CancellationGuard<'_>);

    /// Converts the internal state to the user-facing return datatype
    fn finalise(&self, problem: &mut P, state: &Self::State) -> Self::Output;
}

pub trait FallibleProcedure<P> {
    type Error: std::error::Error + 'static + Send + Sync;

    type Output;

    type State;

    /// An identifier for the procedure.
    ///
    /// This identifier is printed in tracing logs
    const NAME: &'static str;

    fn initialise_fallible(
        &self,
        _problem: &mut P,
        _state: &mut Self::State,
    ) -> Result<(), Self::Error>;

    fn step_fallible(
        &self,
        problem: &mut P,
        state: &mut Self::State,
        guard: CancellationGuard<'_>,
    ) -> Result<(), Self::Error>;

    fn finalise_fallible(
        &self,
        problem: &mut P,
        state: &Self::State,
    ) -> Result<Self::Output, Self::Error>;
}

pub struct Infallible<Proc>(pub Proc);

impl<Proc> Deref for Infallible<Proc> {
    type Target = Proc;
    fn deref(&self) -> &Self::Target {
        &self.0
    }
}

impl<Proc, P> FallibleProcedure<P> for Infallible<Proc>
where
    Proc: Procedure<P>,
{
    const NAME: &'static str = <Proc as Procedure<P>>::NAME;
    type State = <Proc as Procedure<P>>::State;
    type Output = <Proc as Procedure<P>>::Output;
    type Error = std::convert::Infallible;

    fn initialise_fallible(
        &self,
        problem: &mut P,
        state: &mut Self::State,
    ) -> Result<(), Self::Error> {
        let _: () = self.initialise(problem, state);
        Ok(())
    }

    fn step_fallible(
        &self,
        problem: &mut P,
        state: &mut Self::State,
        guard: CancellationGuard<'_>,
    ) -> Result<(), Self::Error> {
        let _: () = self.step(problem, state, guard);
        Ok(())
    }

    fn finalise_fallible(
        &self,
        problem: &mut P,
        state: &Self::State,
    ) -> Result<Self::Output, Self::Error> {
        Ok(self.finalise(problem, state))
    }
}