solverforge-scoring 0.8.4

Incremental constraint scoring for SolverForge
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
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163

use std::hash::Hash;
use std::marker::PhantomData;

use solverforge_core::score::Score;

use super::super::collection_extract::CollectionExtract;
use super::super::filter::{AndBiFilter, BiFilter, FnBiFilter, TrueFilter};
use super::super::flattened_bi_stream::FlattenedBiConstraintStream;

/* Zero-erasure constraint stream over cross-entity pairs.

`CrossBiConstraintStream` joins entities from collection A with collection B,
accumulates filters on joined pairs, and finalizes into an
`IncrementalCrossBiConstraint` via `penalize()` or `reward()`.
*/
pub struct CrossBiConstraintStream<S, A, B, K, EA, EB, KA, KB, F, Sc>
where
    Sc: Score,
{
    pub(super) extractor_a: EA,
    pub(super) extractor_b: EB,
    pub(super) key_a: KA,
    pub(super) key_b: KB,
    pub(super) filter: F,
    pub(super) _phantom: PhantomData<(fn() -> S, fn() -> A, fn() -> B, fn() -> K, fn() -> Sc)>,
}

impl<S, A, B, K, EA, EB, KA, KB, Sc>
    CrossBiConstraintStream<S, A, B, K, EA, EB, KA, KB, TrueFilter, Sc>
where
    S: Send + Sync + 'static,
    A: Clone + Send + Sync + 'static,
    B: Clone + Send + Sync + 'static,
    K: Eq + Hash + Clone + Send + Sync,
    EA: CollectionExtract<S, Item = A>,
    EB: CollectionExtract<S, Item = B>,
    KA: Fn(&A) -> K + Send + Sync,
    KB: Fn(&B) -> K + Send + Sync,
    Sc: Score + 'static,
{
    pub fn new(extractor_a: EA, extractor_b: EB, key_a: KA, key_b: KB) -> Self {
        Self {
            extractor_a,
            extractor_b,
            key_a,
            key_b,
            filter: TrueFilter,
            _phantom: PhantomData,
        }
    }
}

impl<S, A, B, K, EA, EB, KA, KB, F, Sc> CrossBiConstraintStream<S, A, B, K, EA, EB, KA, KB, F, Sc>
where
    S: Send + Sync + 'static,
    A: Clone + Send + Sync + 'static,
    B: Clone + Send + Sync + 'static,
    K: Eq + Hash + Clone + Send + Sync,
    EA: CollectionExtract<S, Item = A>,
    EB: CollectionExtract<S, Item = B>,
    KA: Fn(&A) -> K + Send + Sync,
    KB: Fn(&B) -> K + Send + Sync,
    F: BiFilter<S, A, B>,
    Sc: Score + 'static,
{
    pub fn new_with_filter(
        extractor_a: EA,
        extractor_b: EB,
        key_a: KA,
        key_b: KB,
        filter: F,
    ) -> Self {
        Self {
            extractor_a,
            extractor_b,
            key_a,
            key_b,
            filter,
            _phantom: PhantomData,
        }
    }

    /* Adds a filter predicate to the stream. */
    pub fn filter<P>(
        self,
        predicate: P,
    ) -> CrossBiConstraintStream<
        S,
        A,
        B,
        K,
        EA,
        EB,
        KA,
        KB,
        AndBiFilter<F, FnBiFilter<impl Fn(&S, &A, &B) -> bool + Send + Sync>>,
        Sc,
    >
    where
        P: Fn(&A, &B) -> bool + Send + Sync,
    {
        CrossBiConstraintStream {
            extractor_a: self.extractor_a,
            extractor_b: self.extractor_b,
            key_a: self.key_a,
            key_b: self.key_b,
            filter: AndBiFilter::new(
                self.filter,
                FnBiFilter::new(move |_s: &S, a: &A, b: &B| predicate(a, b)),
            ),
            _phantom: PhantomData,
        }
    }

    /* Expands items from entity B into separate (A, C) pairs with O(1) lookup. */
    pub fn flatten_last<C, CK, Flatten, CKeyFn, ALookup>(
        self,
        flatten: Flatten,
        c_key_fn: CKeyFn,
        a_lookup_fn: ALookup,
    ) -> FlattenedBiConstraintStream<
        S,
        A,
        B,
        C,
        K,
        CK,
        EA,
        EB,
        KA,
        KB,
        Flatten,
        CKeyFn,
        ALookup,
        super::super::filter::TrueFilter,
        Sc,
    >
    where
        C: Clone + Send + Sync + 'static,
        CK: Eq + Hash + Clone + Send + Sync,
        Flatten: Fn(&B) -> &[C] + Send + Sync,
        CKeyFn: Fn(&C) -> CK + Send + Sync,
        ALookup: Fn(&A) -> CK + Send + Sync,
    {
        FlattenedBiConstraintStream::new(
            self.extractor_a,
            self.extractor_b,
            self.key_a,
            self.key_b,
            flatten,
            c_key_fn,
            a_lookup_fn,
        )
    }
}

impl<S, A, B, K, EA, EB, KA, KB, F, Sc: Score> std::fmt::Debug
    for CrossBiConstraintStream<S, A, B, K, EA, EB, KA, KB, F, Sc>
{
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("CrossBiConstraintStream").finish()
    }
}