+ String getRegularExpression();
+
+ /**
+ * Returns a raw regular expression as it was declared in a source.
+ *
+ * @return argument of pattern statement as it was declared in a source.
+ */
+ // FIXME: version 2.0.0: make this method non-default
+ default String getRawRegularExpression() {
+ return getRegularExpression();
+ }
+
+ /**
+ * All implementations should override this method.
+ * The default definition of this method is used only in YANG 1.0 (RFC6020)
+ * implementations of PatternConstraint which do not support modifier statement.
+ * YANG pattern statement has been changed in YANG 1.1 (RFC7950) and now allows modifier statement.
+ *
+ * @return enum constant which represents the value of modifier statement
+ */
+ // FIXME: version 2.0.0: make this method non-default
+ @Nullable default ModifierKind getModifier() {
+ return null;
+ }