Trait Specification 

pub trait Specification<T: ?Sized> {
    // Required method
    fn is_satisfied_by(&self, candidate: &T) -> bool;

    // Provided methods
    fn and<Other>(self, other: Other) -> And<Self, Other>
       where Self: Sized,
             Other: Specification<T> { ... }
    fn or<Other>(self, other: Other) -> Or<Self, Other>
       where Self: Sized,
             Other: Specification<T> { ... }
    fn not(self) -> Not<Self>
       where Self: Sized { ... }
}

A deterministic boolean rule over a borrowed candidate.

Implement this trait for a focused business rule, then compose it with the provided boolean combinators. Evaluation borrows the candidate, so rules do not take ownership of the value they inspect.

Required Methods

fn is_satisfied_by(&self, candidate: &T) -> bool

Returns whether candidate satisfies this rule.

Provided Methods

fn and<Other>(self, other: Other) -> And<Self, Other>

where Self: Sized, Other: Specification<T>,

Combines this rule with other using short-circuiting logical AND.

The resulting And evaluates this rule first. It evaluates other only when this rule returns true.

fn or<Other>(self, other: Other) -> Or<Self, Other>

where Self: Sized, Other: Specification<T>,

Combines this rule with other using short-circuiting logical OR.

The resulting Or evaluates this rule first. It evaluates other only when this rule returns false.

fn not(self) -> Not<Self>

where Self: Sized,

Creates a rule that negates this rule’s result.

Dyn Compatibility

This trait is dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors

impl<T: ?Sized, Inner> Specification<T> for Not<Inner>

where Inner: Specification<T>,

impl<T: ?Sized, Left, Right> Specification<T> for And<Left, Right>

where Left: Specification<T>, Right: Specification<T>,

impl<T: ?Sized, Left, Right> Specification<T> for Or<Left, Right>

where Left: Specification<T>, Right: Specification<T>,

impl<T: ?Sized, Predicate> Specification<T> for Predicate

where Predicate: Fn(&T) -> bool,

impl<T: ?Sized, SpecificationType> Specification<T> for AllOf<'_, SpecificationType>

where SpecificationType: Specification<T>,

impl<T: ?Sized, SpecificationType> Specification<T> for AnyOf<'_, SpecificationType>

where SpecificationType: Specification<T>,

impl<T: ?Sized> Specification<T> for Always

impl<T: ?Sized> Specification<T> for BoxedSpecification<T>

impl<T: ?Sized> Specification<T> for Never

impl<T: ?Sized> Specification<T> for SharedSpecification<T>

impl<UserData, ClockType> Specification<EvaluationContext<UserData>> for Cooldown<ClockType>

where ClockType: Clock,

impl<UserData> Specification<EvaluationContext<UserData>> for Flag

impl<UserData> Specification<EvaluationContext<UserData>> for MaxCount