anchor.diff:    if (!dir.existsSync()) {
       dir.createSync(recursive: true);
     }
  -}+}
  
positive.code: library polymorphic.grind;
  
  import "package:grinder/grinder.dart";
  
  void main(List<String> args) {
    task("clean", defaultClean);
  
negative.code: 
  package(GrinderContext context) {
    ensureOutDirectory();
    var pubspec = loadYaml(new File("pubspec.yaml").readAsStringSync());
    var version = pubspec["version"];
    
    var args = [
      "--enable-experimental-mirrors",
  