core() {
    gulp.watch(['./src/core/**/*.js'], gulp.series(['core-js', 'core-components']));
    gulp.watch(['./src/core/**/*.d.ts'], gulp.series('core-typings'));
    gulp.watch('./src/**/**/*.less', gulp.series(['core-styles', 'core-components']));
  }
/*.js'], gulp.series('core-js', 'core-components'));
    gulp.watch(['./src/core/*