예제 #1
0
  /**
   * Returns all facts in the model.
   *
   * @return the facts.
   */
  public final Formula facts() {
    // sig File extends Object {} { some d: Dir | this in d.entries.contents }
    final Variable file = Variable.unary("this");
    final Variable d = Variable.unary("d");
    final Formula f0 =
        file.in(d.join(entries).join(contents)).forSome(d.oneOf(Dir)).forAll(file.oneOf(File));

    //		sig Dir extends Object {
    //			  entries: set DirEntry,
    //			  parent: lone Dir
    //			} {
    //			  parent = this.~@contents.~@entries
    //			  all e1, e2 : entries | e1.name = e2.name => e1 = e2
    //			  this !in this.^@parent
    //			  this != Root => Root in this.^@parent
    //			}

    final Variable dir = Variable.unary("this");
    final Variable e1 = Variable.unary("e1"), e2 = Variable.unary("e2");

    final Formula f1 =
        (dir.join(parent)).eq(dir.join(contents.transpose()).join(entries.transpose()));
    final Expression e0 = dir.join(entries);
    final Formula f2 =
        e1.join(name).eq(e2.join(name)).implies(e1.eq(e2)).forAll(e1.oneOf(e0).and(e2.oneOf(e0)));
    final Formula f3 = dir.in(dir.join(parent.closure())).not();
    final Formula f4 = dir.eq(Root).not().implies(Root.in(dir.join(parent.closure())));
    final Formula f5 = f1.and(f2).and(f3).and(f4).forAll(dir.oneOf(Dir));

    //		one sig Root extends Dir {} { no parent }
    final Formula f6 = Root.join(parent).no();

    //		sig DirEntry {
    //			  name: Name,
    //			  contents: Object
    //			} { one this.~entries }

    final Variable entry = Variable.unary("this");
    final Formula f7 = entry.join(entries.transpose()).one().forAll(entry.oneOf(DirEntry));

    //		fact OneParent {
    //		    // all directories besides root xhave one parent
    //		    all d: Dir - Root | one d.parent
    //		}

    final Formula f8 = d.join(parent).one().forAll(d.oneOf(Dir.difference(Root)));

    return f0.and(f5).and(f6).and(f7).and(f8);
  }
예제 #2
0
 /**
  * Returns the no aliases assertion.
  *
  * @return the no aliases assertion.
  */
 public final Formula noDirAliases() {
   // all o: Dir | lone o.~contents
   final Variable o = Variable.unary("o");
   return o.join(contents.transpose()).lone().forAll(o.oneOf(Dir));
 }