use std::fmt::Debug;
use crate::semirings::Semiring;
use crate::{StateId, TrsVec};
pub trait FstCache<W: Semiring>: Debug {
fn get_start(&self) -> Option<Option<StateId>>;
fn insert_start(&self, id: Option<StateId>);
fn get_trs(&self, id: StateId) -> Option<TrsVec<W>>;
fn insert_trs(&self, id: StateId, trs: TrsVec<W>);
fn get_final_weight(&self, id: StateId) -> Option<Option<W>>;
fn insert_final_weight(&self, id: StateId, weight: Option<W>);
fn num_known_states(&self) -> usize;
fn num_trs(&self, id: StateId) -> Option<usize>;
fn num_input_epsilons(&self, id: usize) -> Option<usize>;
fn num_output_epsilons(&self, id: usize) -> Option<usize>;
fn len_trs(&self) -> usize;
fn len_final_weights(&self) -> usize;
}