add If Not Contains
open fun <T : Node> addIfNotContains(collection: MutableCollection<PropertyEdge<T>>, declaration: T)
open fun <T : Node> addIfNotContains(collection: MutableCollection<PropertyEdge<T>>, declaration: T, outgoing: Boolean)
Adds a declaration to a collection of property edges, which contain the declarations
Parameters
collection
the collection
declaration
the declaration
outgoing
whether the property is outgoing