@spec allowed([t()], state(), nil | event()) :: [state()]

Returns the list of all the transitions, matching the from state and the event.

Used internally for the validations.

iex> {:ok, transitions} =
...>   Finitomata.PlantUML.parse("[*] --> s1 : foo\ns1 --> s2 : ok\ns2 --> [*] : ko")
...> Finitomata.Transition.allowed(transitions, :s1, :foo)
[:s2]
...> Finitomata.Transition.allowed(transitions, :s1, :*)
[]

@spec allowed?([t()], state(), state()) :: boolean()

Returns true if the transition from → to is allowed, false otherwise.

iex> {:ok, transitions} =
...>   Finitomata.PlantUML.parse("[*] --> s1 : foo\ns1 --> s2 : ok\ns2 --> [*] : ko")
...> Finitomata.Transition.allowed?(transitions, :s1, :s2)
true
...> Finitomata.Transition.allowed?(transitions, :s1, :*)
false

@spec entry([t()]) :: state()

Returns the state after starting one, so-called entry state.

iex> {:ok, transitions} =
...>   Finitomata.PlantUML.parse("[*] --> s1 : foo\ns1 --> s2 : ok\ns2 --> [*] : ko")
...> Finitomata.Transition.entry(transitions)
:s1

@spec responds?([t()], state(), event()) :: boolean()

Returns true if the state from hsa an outgoing transition with event, false otherwise.

iex> {:ok, transitions} =
...>   Finitomata.PlantUML.parse("[*] --> s1 : foo\ns1 --> s2 : ok\ns2 --> [*] : ko")
...> Finitomata.Transition.responds?(transitions, :s1, :ok)
true
...> Finitomata.Transition.responds?(transitions, :s1, :ko)
false

@spec states([t()]) :: [state()]

Returns the not ordered list of states, excluding the starting and ending states :*.

iex> {:ok, transitions} =
...>   Finitomata.PlantUML.parse("[*] --> s1 : foo\ns1 --> s2 : ok\ns2 --> [*] : ko")
...> Finitomata.Transition.states(transitions)
[:s1, :s2]