Added documentation for Action{,Err,s}.

action.go

@@ -1,7 +1,9 @@
 package zntg
 
+// Action is a method without arguments or return values.
 type Action func()
 
+// Err converts the Action to an ActionErr.
 func (a Action) Err() ActionErr {
 	return func() error {
 		a()
@@ -9,24 +11,30 @@ func (a Action) Err() ActionErr {
 	}
 }
 
+// ActionErr is a method that only returns an error.
 type ActionErr func() error
 
+// Actions is a slice of ActionErr's.
 type Actions []ActionErr
 
+// Add adds an Action and returns the new list of Actions.
 func (a Actions) Add(fn Action) Actions {
 	return a.AddErr(fn.Err())
 }
 
+// AddErr adds an ActionErr and return the new list of Actions.
 func (a Actions) AddErr(fn ActionErr) Actions {
 	return append(a, fn)
 }
 
+// Do executes all actions.
 func (a Actions) Do() {
 	for _, a := range a {
 		a()
 	}
 }
 
+// DoErr executes all actions but stops on the first action that returns an error.
 func (a Actions) DoErr() error {
 	for _, a := range a {
 		if err := a(); err != nil {