Adding modding folder with a hacked build.

modding/hacked/editor/values/Unifier.go

@@ -0,0 +1,107 @@
+package values
+
+// Unifier can be used to verify whether a list of values has equal entries.
+type Unifier struct {
+	state unifierState
+}
+
+// NewUnifier returns a new instance.
+func NewUnifier() Unifier {
+	return Unifier{state: unifierInitState{}}
+}
+
+// UnifierFor returns a unifier for a single value.
+func UnifierFor(value interface{}) Unifier {
+	unifier := NewUnifier()
+	unifier.Add(value)
+	return unifier
+}
+
+// Add unifies the given value to the current state.
+// The given value must be comparable.
+func (u *Unifier) Add(value interface{}) {
+	u.state = u.state.add(value)
+}
+
+// Unified returns the result of the unification.
+// If all values that were added to the unifier were equal, then the first
+// added value will be returned. Otherwise, nil will be returned.
+func (u *Unifier) Unified() interface{} {
+	return u.state.unified()
+}
+
+// IsUnique returns true if the unifier has received only equal values.
+func (u Unifier) IsUnique() bool {
+	return u.state.isUnique()
+}
+
+// IsEmpty returns true if the unifier has not received any value.
+func (u Unifier) IsEmpty() bool {
+	return (u.state == nil) || u.state.isEmpty()
+}
+
+type unifierState interface {
+	add(value interface{}) unifierState
+	unified() interface{}
+	isUnique() bool
+	isEmpty() bool
+}
+
+type unifierInitState struct{}
+
+func (state unifierInitState) add(value interface{}) unifierState {
+	return unifierMatchedState{value: value}
+}
+
+func (state unifierInitState) unified() interface{} {
+	return nil
+}
+
+func (state unifierInitState) isUnique() bool {
+	return false
+}
+
+func (state unifierInitState) isEmpty() bool {
+	return true
+}
+
+type unifierMatchedState struct {
+	value interface{}
+}
+
+func (state unifierMatchedState) add(value interface{}) unifierState {
+	if state.value == value {
+		return state
+	}
+	return unifierMismatchedState{}
+}
+
+func (state unifierMatchedState) unified() interface{} {
+	return state.value
+}
+
+func (state unifierMatchedState) isUnique() bool {
+	return true
+}
+
+func (state unifierMatchedState) isEmpty() bool {
+	return false
+}
+
+type unifierMismatchedState struct{}
+
+func (state unifierMismatchedState) add(value interface{}) unifierState {
+	return state
+}
+
+func (state unifierMismatchedState) unified() interface{} {
+	return nil
+}
+
+func (state unifierMismatchedState) isUnique() bool {
+	return false
+}
+
+func (state unifierMismatchedState) isEmpty() bool {
+	return false
+}