# 只重新编译被更改过的文件 通过使用 [`gulp-watch`](https://github.com/floatdrop/gulp-watch): ``` var gulp = require('gulp'); var sass = require('gulp-sass'); var watch = require('gulp-watch'); gulp.task('default', function() { return gulp.src('sass/*.scss') .pipe(watch('sass/*.scss')) .pipe(sass()) .pipe(gulp.dest('dist')); }); ```