lang

type Either[L, R any] interface {
	// IsLeft returns true if the Either instance is a Left.
	IsLeft() bool
	// Left returns the left value.
	Left() L
	// IsRight returns true if the Either instance is a Right.
	IsRight() bool
	// Right returns the right value.
	Right() R
}

type Option[T any] interface {
	// IsDefined returns true if the Option instance is defined.
	IsDefined() bool
	// IsEmpty returns true if the Option instance is empty.
	IsEmpty() bool
	// Get returns the value of the Option instance.
	Get() T
	// GetOrElse returns the value of the Option instance if it is defined. Otherwise, it returns the given default value.
	GetOrElse(defaultValue T) T
}

type Tuple2[A any, B any] interface {
	// A returns the first element of the tuple.
	A() A
	// B returns the second element of the tuple.
	B() B
}

type Tuple3[A any, B any, C any] interface {
	// A returns the first element of the tuple.
	A() A
	// B returns the second element of the tuple.
	B() B
	// C returns the third element of the tuple.
	C() C
}