How to use the pathwatcher.watch function in pathwatcher

this.gitRepo.getPath().then(gitDirPath => {
      // Watch the git dir path. We're really just interested in the index file,
      // but watching it directly is Tricky because it's written atomically
      // which looks like a delete + create.
      const watcher = PatchWatcher.watch(gitDirPath, () => this.didChange())
      this.subscriptions.add(new Disposable(() => watcher.close()))
    })
  }

this.gitRepo.getPath().then(gitDirPath => {
      // Watch the git dir path. We're really just interested in the index file,
      // but watching it directly is Tricky because it's written atomically
      // which looks like a delete + create.
      const watcher = PatchWatcher.watch(gitDirPath, () => this.didChange())
      this.subscriptions.add(new Disposable(() => watcher.close()))
    })
  }

setTimeout(function(){
      var pathwatcher = require('pathwatcher');
      pathwatcher.watch(module.filename, /*{persistent: true},*/ function () {
        clearTimeout(timeout);
        timeout = setTimeout(function () {
          hotCompile(module, module.filename, true);
          console.log('hot reloaded '+module.filename);
        }, 100);
      });
    },100);
  }

stylePaths.forEach((stylePath) => {
        if (!stylePath.endsWith('.less')) {
          return;
        }
        PathWatcher.watch(stylePath, () => {
          const styleEl = document.head.querySelector(`[source-path="${stylePath}"]`);
          styleEl.textContent = this.loadStylesheet(styleEl.sourcePath, true);
        });
      });
    };