| --import '/org.eclipse.emf.examples.library/model/extlibrary.ecore' |
| |
| package extlibrary |
| |
| context Library |
| -- get all books with a title in a library and its branches (recursively) |
| def: getBooks(title : String) : Set(Book) = |
| books->select(b | b.title = title)->asSet()->union( |
| branches.getBooks(title)->asSet()) |
| |
| context Book |
| -- the library containing a book |
| def: library : Library = Library.allInstances()->any(books->includes(self)) |
| |
| -- book titles are unique within their library branch (and its sub-branches) |
| inv unique_title: not library.oclIsUndefined() implies |
| library.getBooks(title) = Set{self} |
| |
| endpackage |
