Planning Solutions

A planning solution is the root struct that represents your entire problem and its current solution state. It holds all entities, problem facts, available values, and the score.

The #[planning_solution] Macro

use solverforge::prelude::*;

#[planning_solution(constraints = "crate::constraints::define_constraints")]
pub struct Schedule {
    #[problem_fact_collection]
    #[value_range_provider]
    pub employees: Vec<Employee>,

    #[problem_fact_collection]
    pub availability: Vec<Availability>,

    #[planning_entity_collection]
    pub shifts: Vec<Shift>,

    #[planning_score]
    pub score: Option<HardSoftScore>,
}

The constraints parameter specifies the module path to the constraint provider function.

Field Attributes

#[planning_entity_collection]

Marks a Vec<T> field containing planning entities. The solver iterates these to find variables to change.

#[planning_entity_collection]
pub shifts: Vec<Shift>,

#[problem_fact_collection]

Marks a Vec<T> field containing immutable problem facts. Used by constraints but never modified by the solver.

#[problem_fact_collection]
pub employees: Vec<Employee>,

#[value_range_provider]

Marks a collection as providing possible values for planning variables. Usually combined with #[problem_fact_collection].

#[problem_fact_collection]
#[value_range_provider]
pub timeslots: Vec<Timeslot>,

The solver draws from this collection when trying assignments for any #[planning_variable] field whose type matches.

#[planning_score]

Marks the field that holds the current solution quality. Must be Option<ScoreType>.

#[planning_score]
pub score: Option<HardSoftScore>,

Supported score types: SoftScore, HardSoftScore, HardMediumSoftScore, HardSoftDecimalScore, BendableScore.

Requirements

• Must derive Clone and Debug (added automatically by the macro)
• Must have exactly one #[planning_score] field
• Must have at least one #[planning_entity_collection] field
• Must have at least one #[value_range_provider] field

See Also

• Planning Entities — What the solver changes
• Score Types — Available score types