Struct rslogic::state::State

pub struct State<T> where
    T: PartialEq + Unif<T>,  { /* fields omitted */ }

A logical state, containing a collection of variable bindings.

Variables are stored with one level of indirection, to indicate variables that have been unified before being bound.

Methods

impl<T> State<T> where
    T: PartialEq + Unif<T>, 

fn empty() -> State<T>

Creates an empty state.

fn binds_var(&self, var: &Var) -> bool

Returns true if the variable is bound in the state.

fn get<'a>(&'a self, var: &Var) -> Option<&'a T>

Returns a reference to the value bound to the variable in the state, or None if the var4iable is not bound.

fn unify_val(&self, var: &Var, val: T) -> PossibleStates<T>

Attempts to unify a variable with a value. If the variable is not bound, returns a new state containing a binding to the value. If the variable is already bound, returns the unification of the two values.

fn unify_var(&self, v1: &Var, v2: &Var) -> PossibleStates<T>

Attempts to unify two variables.

fn make_var(&self) -> (Var, State<T>)

Creates a new variable and a new state with which it is usable.

Trait Implementations

impl<T> Clone for State<T> where
    T: PartialEq + Unif<T>, 

fn clone(&self) -> State<T>

Returns a copy of the value.

fn clone_from(&mut self, source: &State<T>)

Performs copy-assignment from source.