11.7.3 Namespace Description

   Constructs::Namespace reuses the definition of Abstractions::Constraints::Namespace.

   A namespace has the ability to import either individual members or all members of a package, thereby making it possible to refer to those named elements without qualification in the importing namespace. In the case of conflicts, it is necessary to use qualified names or aliases to disambiguate the referenced elements.

   • “NamedElement? on page 143

   No additional attributes

• elementImport: ElementImport [*] References the ElementImports owned by the Namespace.Subsets Element::ownedElement.

• /importedMember: PackageableElement [*] References the PackageableElements that are members of this Namespace as a result of either PackageImports or ElementImports. Subsets Namespace::member.

• /member: NamedElement [*] Redefines the corresponding property of Abstractions::Namespaces::Namespace.

• /ownedMember: NamedElement [*] Redefines the corresponding property of Abstractions::Namespaces::Namespace.

• packageImport: PackageImport [*] References the PackageImports owned by the Namespace. Subsets Element::ownedElement.

   [1] The importedMember property is derived from the ElementImports and the PackageImports.

   self.importedMember->includesAll(self.importMembers(self.elementImport.importedElement.asSet()->union(self.packageImport.importedPackage->collect(p | p.visibleMembers()))))

   [1] The query getNamesOfMember() is overridden to take account of importing. It gives back the set of names that an element would have in an importing namespace, either because it is owned; or if not owned, then imported individually; or if not individually, then from a package.

   Namespace::getNamesOfMember(element: NamedElement): Set(String);getNamesOfMember=if self.ownedMember ->includes(element)then Set{}->include(element.name)else let elementImports: ElementImport = self.elementImport->select(ei | ei.importedElement = element) inif elementImports->notEmpty()then elementImports->collect(el | el.getName())else

   self.packageImport->select(pi | pi.importedPackage.visibleMembers()->includes(element))-> collect(pi | pi.importedPackage.getNamesOfMember(element))

   endifendif

   [2] The query importMembers() defines which of a set of PackageableElements are actually imported into the namespace. This excludes hidden ones, i.e., those which have names that conflict with names of owned members, and also excludes elements that would have the same name when imported.

   Namespace::importMembers(imps: Set(PackageableElement)): Set(PackageableElement);importMembers = self.excludeCollisions(imps)->select(imp | self.ownedMember->forAll(mem | mem.imp.isDistinguishableFrom(mem, self)))

   [3] The query excludeCollisions() excludes from a set of PackageableElements any that would not be distinguishable from each other in this namespace.

   Namespace::excludeCollisions(imps: Set(PackageableElements)): Set(PackageableElements);excludeCollisions = imps->reject(imp1 | imps.exists(imp2 | not imp1.isDistinguishableFrom(imp2, self)))

   No additional semantics

   No additional notation