func (g *Group) takeLastComment() (last *Comment) {
	last, g.Elements = takeLastComment(g.Elements)
	return
}
takeLastComment is part of elementContainer
removes and returns the last element of the list if it is a Comment.
package proto
import (
	"text/scanner"
)
type Group struct {
	Position scanner.Position
	Comment  *Comment
	Name     string
	Optional bool
	Repeated bool
	Required bool
	Sequence int
	Elements []Visitee
}
func (g *Group) Accept(v Visitor) {
	v.VisitGroup(g)
}
func (g *Group) addElement(v Visitee) {
	g.Elements = append(g.Elements, v)
}
func (g *Group) elements() []Visitee {
	return g.Elements
}
func (g *Group) Doc() *Comment {
	return g.Comment
}