anchor.diff:    @override
     Iterable<AstNode> get children => <AstNode>[expression];
   
  -  ExpressionStatement(this.expression,
  -      {@required List<Label> labels, @required AstNode parent})
  +  ExpressionStatement(
  +      {@required this.expression,
  +      @required List<Label> labels,
  +      @required AstNode parent})
         : super(labels, parent);
   }
   
  
positive.code: class PointerType extends VariableType {
    VariableType target;
  
    PointerType(String identifier, int size, this.target)
        : super(identifier, size);
  }
  
  /// Represents a variable definition in an expression, a function argument list,
  /// or the global namespace.
  class Variable extends Definition {
    Token variableTypeName;
    Token variableName;
    VariableType variableType;
  
negative.code:     yield* statements;
    }
  
    CompoundStatement(
        {@required this.openingBracket,
        @required List<Label> labels,
        @required AstNode parent})
        : super(labels, parent);
  }
  
  