Struct KeysConstraint 

pub struct KeysConstraint<S: ValueSchema, R, K, V>
where
    R: Deref<Target = HashMap<K, V>>,
{ /* private fields */ }

Constrains a variable to keys present in a HashMap.

Created via the ContainsConstraint trait (.has(variable)). Proposals enumerate every key in the map; confirmations retain only proposals whose key exists. Accepts &HashMap<K,V>, Rc<HashMap<K,V>>, and Arc<HashMap<K,V>>.

Implementations

impl<S: ValueSchema, R, K, V> KeysConstraint<S, R, K, V>

where R: Deref<Target = HashMap<K, V>>,

pub fn new(variable: Variable<S>, map: R) -> Self

Creates a constraint that restricts variable to keys in map.

Trait Implementations

impl<'a, S: ValueSchema, R, K, V> Constraint<'a> for KeysConstraint<S, R, K, V>

where K: 'a + Eq + Hash + for<'b> TryFromValue<'b, S>, for<'b> &'b K: ToValue<S>, V: 'a, R: Deref<Target = HashMap<K, V>>,

fn variables(&self) -> VariableSet

Returns the set of variables this constraint touches.

fn estimate(&self, variable: VariableId, _binding: &Binding) -> Option<usize>

Estimates the number of candidate values for variable given the current partial binding.

fn propose( &self, variable: VariableId, _binding: &Binding, proposals: &mut Vec<RawValue>, )

Enumerates candidate values for variable into proposals.

fn confirm( &self, variable: VariableId, _binding: &Binding, proposals: &mut Vec<RawValue>, )

Filters proposals to remove values for variable that violate this constraint.

fn satisfied(&self, _binding: &Binding) -> bool

Returns whether this constraint is consistent with the current binding.

fn influence(&self, variable: VariableId) -> VariableSet

Returns the set of variables whose estimates may change when variable is bound or unbound.