add access method for variables bar on pattern in bar notation

aaccess2/src/access/TreeAccess.cpp

@@ -25,6 +25,9 @@ std::string TreeAccess::access ( const std::string & component ) {
 	if ( settings == TreeSettings::Settings::NONLINEAR_VARIABLES )
 		return "tree::NonlinearAlphabet";
+	if ( settings == TreeSettings::Settings::VARIABLES_BAR )
+		return "tree::VariablesBarSymbol";
+
 	throw exception::CommonException ( "Component not available" );
 }

aaccess2/src/access/settings/TreeSettings.h

@@ -15,7 +15,7 @@ namespace dataAccess {
 class TreeEnum {
 public:
 	enum class Settings {
-		ALPHABET, CONTENT, SUBTREE_WILDCARD, NONLINEAR_VARIABLES, __MAX__
+		ALPHABET, CONTENT, SUBTREE_WILDCARD, NONLINEAR_VARIABLES, VARIABLES_BAR, __MAX__
 	};
 	static std::string toString ( TreeEnum::Settings settings ) {
@@ -32,6 +32,9 @@ public:
 		case TreeEnum::Settings::NONLINEAR_VARIABLES:
 			return "nonlinear_variables";
+		case TreeEnum::Settings::VARIABLES_BAR:
+			return "variables_bar";
+
 		case TreeEnum::Settings::__MAX__:
 			throw exception::CommonException ( "Invalid enumeration" );
 		}