Struct FirstFail

pub struct FirstFail<Var, TieBreaking> { /* private fields */ }

A VariableSelector which selects the variable with the smallest domain (based on the lower-bound and upper-bound, disregarding holes).

Uses a TieBreaker to break ties, the default is the InOrderTieBreaker but it is possible to construct the variable selector with a custom TieBreaker by using the method FirstFail::with_tie_breaker.

Implementations

impl<Var: Clone> FirstFail<Var, InOrderTieBreaker<Var, i32>>

pub fn new(variables: &[Var]) -> Self

impl<Var: Clone + 'static, TieBreaking: TieBreaker<Var, i32>> FirstFail<Var, TieBreaking>

pub fn with_tie_breaker(variables: &[Var], tie_breaker: TieBreaking) -> Self

Trait Implementations

impl<Var, TieBreaking> Debug for FirstFail<Var, TieBreaking>

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl<TieBreaking> VariableSelector<DomainId> for FirstFail<DomainId, TieBreaking>

where TieBreaking: TieBreaker<DomainId, i32>,

fn select_variable( &mut self, context: &SelectionContext<'_>, ) -> Option<DomainId>

Determines which variable to select next if there are any left to branch on. Should only return None when all variables which have been passed to the VariableSelector have been assigned. Otherwise it should return the variable to branch on next.

fn on_conflict(&mut self)

A function which is called after a conflict has been found and processed but (currently) does not provide any additional information.

fn on_unassign_literal(&mut self, _literal: Literal)

A function which is called after a Literal is unassigned during backtracking (i.e. when it was fixed but is no longer), specifically, it provides literal which is the Literal which has been reset. This method could thus be called multiple times in a single backtracking operation by the solver.

fn on_unassign_integer(&mut self, _variable: DomainId, _value: i32)

A function which is called after a DomainId is unassigned during backtracking (i.e. when it was fixed but is no longer), specifically, it provides variable which is the DomainId which has been reset. This method could thus be called multiple times in a single backtracking operation by the solver.

fn on_appearance_in_conflict_literal(&mut self, _literal: Literal)

A function which is called when a Literal appears in a conflict during conflict analysis.

fn on_appearance_in_conflict_integer(&mut self, _variable: DomainId)

A function which is called when a variable appears in a conflict during conflict analysis.

fn is_restart_pointless(&mut self) -> bool

This method returns whether a restart is currently pointless for the VariableSelector.