gulp some tips

var gulp = require(‘gulp‘);
var coffee = require(‘gulp-coffee‘);
var concat = require(‘gulp-concat‘);
function handleError(error){
  console.log(error);
  this.emit(‘end‘);    
}
gulp.task(‘coffee‘,function(){
    return gulp.src(‘src/*.coffee‘)
                     .pipe(coffee())
                     .on(‘error‘,handleError)
                     .pipe(concat(‘all.js‘).pipe(gulp.dest(‘dist/‘));
});                           
gulp.task(‘watch‘, [‘coffee‘], function(){
           gulp.watch(‘src/*.coffee‘,[‘coffee‘]);
});