True if this node (and all its sub-nodes) is a valid archetype node for its type. This function should
be implemented by each subtype to perform semantic validation of itself, and then call the is_valid
function in any subparts, and generate the result appropriately.

Declaration :

• Uml : abstract, + is_valid() : Boolean
• C++ : public: virtual bool is_valid()= 0
• Java : public abstract boolean is_valid()

True if the relative path a_path exists at this node.

Declaration :

• Uml : + has_path(in a_path : String) : Boolean
• C++ : public: bool has_path()
• Java : public boolean has_path()

Path of this node relative to root of archetype.

Declaration :

• Uml : + path() : String
• C++ : public: string path()
• Java : public String path()

True if constraints represented by other are narrower than this node.
Note: not easily evaluatable for CONSTRAINT_REF nodes.

Declaration :

• Uml : abstract, + is_subset_of(in other : ARCHETYPE_CONSTRAINT) : Boolean
• C++ : public: virtual bool is_subset_of()= 0
• Java : public abstract boolean is_subset_of()