Struct FirstMatch 

pub struct FirstMatch<T: ?Sized, Decision> { /* private fields */ }

Ordered, typed decisions selected by the first matching specification.

Rules are evaluated in insertion order. The first satisfied rule wins and later rules are not evaluated.

Implementations

impl<T: ?Sized, Decision> FirstMatch<T, Decision>

pub const fn new() -> Self

Creates a first-match decision set with no rules.

pub fn push<Concrete>(&mut self, specification: Concrete, decision: Decision)

where Concrete: Specification<T> + 'static,

Appends a rule and its decision, preserving evaluation order.

pub fn decide_or<'decision>( &'decision self, candidate: &T, fallback: &'decision Decision, ) -> &'decision Decision

Returns the first matching decision or fallback when no rule matches.

Trait Implementations

impl<T: ?Sized, Decision> DecisionSpecification<T> for FirstMatch<T, Decision>

type Decision = Decision

The decision selected by this rule.

fn decide(&self, candidate: &T) -> Option<&Decision>

Returns the selected decision, or None when no rule matches.

impl<T: ?Sized, Decision> Default for FirstMatch<T, Decision>

fn default() -> Self

Returns the “default value” for a type.