solve-classic/it.unibo.tuprolog.solve.classic.fsm/AbstractEndState

AbstractEndState

abstract class AbstractEndState(val solution: Solution, val context: ClassicExecutionContext) : AbstractState, EndState

Common base of the two terminal EndStates (StateEnd and StateHalt). By default there is no further transition from here (computeNext throws); StateEnd overrides this to loop back into StateBacktracking when ClassicExecutionContext.hasOpenAlternatives is true, which is what makes it a resumable terminal, unlike StateHalt, the one true sink of the machine.

Inheritors

Constructors

AbstractEndState

constructor(solution: Solution, context: ClassicExecutionContext)

Properties

open override val context: ClassicExecutionContext

The execution context this state operates on.

hasOpenAlternatives

open val hasOpenAlternatives: Boolean

Whether asking for another solution after this one would resume resolution (via backtracking) rather than truly stop.

open val isEndState: Boolean

Whether this state is a terminal one for the current resolution step, i.e. an EndState.

open override val solution: Solution

The solution emitted by reaching this state.

Functions

open fun asEndState(): EndState

This state as an EndState, or null if isEndState is false.

open fun castToEndState(): EndState

This state as an EndState.

abstract fun clone(context: ClassicExecutionContext = this.context): State

Returns a copy of this state, replacing context with the given one (defaulting to the current context).

open override fun next(): State

Computes the state the machine transitions into from here -- a pure function of context.