solverforge_scoring/stream/

penta_stream.rs

/* Zero-erasure penta-constraint stream for five-entity constraint patterns.

A `PentaConstraintStream` operates on quintuples of entities and supports
filtering, weighting, and constraint finalization. All type information
is preserved at compile time - no Arc, no dyn.

# Example

```
use solverforge_scoring::stream::ConstraintFactory;
use solverforge_scoring::stream::joiner::equal;
use solverforge_scoring::api::constraint_set::IncrementalConstraint;
use solverforge_core::score::SoftScore;

#[derive(Clone, Debug, Hash, PartialEq, Eq)]
struct Task { team: u32 }

#[derive(Clone)]
struct Solution { tasks: Vec<Task> }

// Penalize when five tasks are on the same team
let constraint = ConstraintFactory::<Solution, SoftScore>::new()
.for_each(|s: &Solution| s.tasks.as_slice())
.join(equal(|t: &Task| t.team))
.join(equal(|t: &Task| t.team))
.join(equal(|t: &Task| t.team))
.join(equal(|t: &Task| t.team))
.penalize(SoftScore::of(1))
.named("Team clustering");

let solution = Solution {
tasks: vec![
Task { team: 1 },
Task { team: 1 },
Task { team: 1 },
Task { team: 1 },
Task { team: 1 },
Task { team: 2 },
],
};

// One quintuple on team 1: (0, 1, 2, 3, 4) = -1 penalty
assert_eq!(constraint.evaluate(&solution), SoftScore::of(-1));
```
*/

super::arity_stream_macros::impl_arity_stream!(
    penta,
    PentaConstraintStream,
    PentaConstraintBuilder
);

// Additional doctests for individual methods

#[cfg(doctest)]
mod doctests {
    /* # Filter method

    ```
    use solverforge_scoring::stream::ConstraintFactory;
    use solverforge_scoring::stream::joiner::equal;
    use solverforge_scoring::api::constraint_set::IncrementalConstraint;
    use solverforge_core::score::SoftScore;

    #[derive(Clone, Debug, Hash, PartialEq, Eq)]
    struct Item { group: u32, value: i32 }

    #[derive(Clone)]
    struct Solution { items: Vec<Item> }

    let constraint = ConstraintFactory::<Solution, SoftScore>::new()
    .for_each(|s: &Solution| s.items.as_slice())
    .join(equal(|i: &Item| i.group))
    .join(equal(|i: &Item| i.group))
    .join(equal(|i: &Item| i.group))
    .join(equal(|i: &Item| i.group))
    .filter(|a: &Item, b: &Item, c: &Item, d: &Item, e: &Item| {
    a.value + b.value + c.value + d.value + e.value > 20
    })
    .penalize(SoftScore::of(1))
    .named("High sum quintuples");

    let solution = Solution {
    items: vec![
    Item { group: 1, value: 3 },
    Item { group: 1, value: 4 },
    Item { group: 1, value: 5 },
    Item { group: 1, value: 6 },
    Item { group: 1, value: 7 },
    ],
    };

    // 3+4+5+6+7=25 > 20, matches
    assert_eq!(constraint.evaluate(&solution), SoftScore::of(-1));
    ```

    # Penalize method

    ```
    use solverforge_scoring::stream::ConstraintFactory;
    use solverforge_scoring::stream::joiner::equal;
    use solverforge_scoring::api::constraint_set::IncrementalConstraint;
    use solverforge_core::score::SoftScore;

    #[derive(Clone, Debug, Hash, PartialEq, Eq)]
    struct Task { priority: u32 }

    #[derive(Clone)]
    struct Solution { tasks: Vec<Task> }

    let constraint = ConstraintFactory::<Solution, SoftScore>::new()
    .for_each(|s: &Solution| s.tasks.as_slice())
    .join(equal(|t: &Task| t.priority))
    .join(equal(|t: &Task| t.priority))
    .join(equal(|t: &Task| t.priority))
    .join(equal(|t: &Task| t.priority))
    .penalize(SoftScore::of(5))
    .named("Quintuple priority conflict");

    let solution = Solution {
    tasks: vec![
    Task { priority: 1 },
    Task { priority: 1 },
    Task { priority: 1 },
    Task { priority: 1 },
    Task { priority: 1 },
    ],
    };

    // One quintuple = -5
    assert_eq!(constraint.evaluate(&solution), SoftScore::of(-5));
    ```

    # Penalize with dynamic weight

    ```
    use solverforge_scoring::stream::ConstraintFactory;
    use solverforge_scoring::stream::joiner::equal;
    use solverforge_scoring::api::constraint_set::IncrementalConstraint;
    use solverforge_core::score::SoftScore;

    #[derive(Clone, Debug, Hash, PartialEq, Eq)]
    struct Task { team: u32, cost: i64 }

    #[derive(Clone)]
    struct Solution { tasks: Vec<Task> }

    let constraint = ConstraintFactory::<Solution, SoftScore>::new()
    .for_each(|s: &Solution| s.tasks.as_slice())
    .join(equal(|t: &Task| t.team))
    .join(equal(|t: &Task| t.team))
    .join(equal(|t: &Task| t.team))
    .join(equal(|t: &Task| t.team))
    .penalize(|a: &Task, b: &Task, c: &Task, d: &Task, e: &Task| {
    SoftScore::of(a.cost + b.cost + c.cost + d.cost + e.cost)
    })
    .named("Team cost");

    let solution = Solution {
    tasks: vec![
    Task { team: 1, cost: 1 },
    Task { team: 1, cost: 2 },
    Task { team: 1, cost: 3 },
    Task { team: 1, cost: 4 },
    Task { team: 1, cost: 5 },
    ],
    };

    // Penalty: 1+2+3+4+5 = -15
    assert_eq!(constraint.evaluate(&solution), SoftScore::of(-15));
    ```

    # Reward method

    ```
    use solverforge_scoring::stream::ConstraintFactory;
    use solverforge_scoring::stream::joiner::equal;
    use solverforge_scoring::api::constraint_set::IncrementalConstraint;
    use solverforge_core::score::SoftScore;

    #[derive(Clone, Debug, Hash, PartialEq, Eq)]
    struct Person { team: u32 }

    #[derive(Clone)]
    struct Solution { people: Vec<Person> }

    let constraint = ConstraintFactory::<Solution, SoftScore>::new()
    .for_each(|s: &Solution| s.people.as_slice())
    .join(equal(|p: &Person| p.team))
    .join(equal(|p: &Person| p.team))
    .join(equal(|p: &Person| p.team))
    .join(equal(|p: &Person| p.team))
    .reward(SoftScore::of(10))
    .named("Team synergy");

    let solution = Solution {
    people: vec![
    Person { team: 1 },
    Person { team: 1 },
    Person { team: 1 },
    Person { team: 1 },
    Person { team: 1 },
    ],
    };

    // One quintuple = +10
    assert_eq!(constraint.evaluate(&solution), SoftScore::of(10));
    ```

    # named method

    ```
    use solverforge_scoring::stream::ConstraintFactory;
    use solverforge_scoring::stream::joiner::equal;
    use solverforge_scoring::api::constraint_set::IncrementalConstraint;
    use solverforge_core::score::SoftScore;

    #[derive(Clone, Debug, Hash, PartialEq, Eq)]
    struct Item { id: usize }

    #[derive(Clone)]
    struct Solution { items: Vec<Item> }

    let constraint = ConstraintFactory::<Solution, SoftScore>::new()
    .for_each(|s: &Solution| s.items.as_slice())
    .join(equal(|i: &Item| i.id))
    .join(equal(|i: &Item| i.id))
    .join(equal(|i: &Item| i.id))
    .join(equal(|i: &Item| i.id))
    .penalize(SoftScore::of(1))
    .named("Quintuple items");

    assert_eq!(constraint.name(), "Quintuple items");
    ```
    */
}