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should

should是一个情态动词单词,与动词原形连用,可以翻译为应该、将会,等等。[1] 

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$ionicHistory API的相关知识 $ionicHistory 定义: $ ionicHistory在用户浏览应用程序时跟踪页面。获取页面信息,进行页面跳转操作。特点:Should a user navigate few pages deep on one tab, and then switch to a new tab and back, the back button relates not to the previous tab

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日更3天|英语学习 文/蓝色33 今天学习几个马云爸爸演讲中的金句。 You should learn from your competitor, but never copy. Copy and you die. 向竞争对手学习,但不要山寨别人。山寨意味着凉凉。 Intelligent people need a fool to lead them. When the team's all a bunch of scientists

iOS Git 提交忽略文件 UserInterfaceState.xcuserstate

gitignore里面 # Xcode # # gitignore contributors: remember to update Global/Xcode.gitignore, Objective-C.gitignore Swift.gitignore ## Build generated build/ DerivedData/ ## Various settings *.gitignore. However # you should judge for yourself, the pros and cons are mentioned at: # https://guides.cocoapods.org/using/using-cocoapods.html#should-i-check-the-pods-directory-into-source-control # # Pods/ # # Add this line if you want to avoid checking in source code from the Xcode workspace # *.

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Nginx CORS 配置 # # Wide-open CORS config for nginx # location / { if ($request_method = 'OPTIONS') { add_header 'Access-Control-Allow-Origin' '*'; add_header 'Access-Control-Allow-Methods' 'GET, POST, OPTIONS'; # # Custom headers and headers various browsers *should* be OK with but aren't # add_header 'Access-Control-Allow-Headers' 'DNT,User-Agent,X-Requested-With,If-Modified-Since,Cache-Control,Content-Type

Laravel 异常处理

} if ($e instanceof \ErrorException) { return xxx; } } } render方法 /** * Render an exception into an HTTP response. * * @param \Illuminate\Http\Request $request * @param \Exception $e * @return \Illuminate\Http\Response */ public function render($request, Exception $e) { //TODO 这里一条自定义http错误自动跳转到首页 if (getenv('APP_ENV') == 'production' $e instanceof HttpException) { Log::error($e);

ES 查询优化(二)

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使用 WebStorm 创建 React App

使用 WebStorm 创建 React App image.png /usr/local/bin/node /usr/local/lib/node_modules/create-react-app/index.js . Done 构建通用的 React 和 Node 应用 原文:Build a universal React and Node App 演示:https://judo-heroes.herokuapp.com/ 译者:nzbin 译者的话:这是一篇非常优秀的 React 教程,该文对 React 组件、React Router 以及 Node 做了很好的梳理。

JUnit测试异常

JUnit测试异常 假如需要测试下面的类: public class Student { public boolean canVote(int age) { if (i =0) throw new IllegalArgumentException("age should be +"); } } 测试抛出的异常有三种方法: @Test ( expected = Throwable.class ) @Test(expected = IllegalArgumentException.class) public void canVoteExp() { Student student = new Student(); student.canVote(0); } catch (IllegalArgumentException e) { assertThat(e.getMessage(), containsString("age should be +"));

Leetcode 210. Course Schedule II

To take course 1 you should have finished course 0. public int[] findOrder(int numCourses, int[][] prerequisites) { //tip 后面的是前置条件 int[] preCount = new int[numCourses]; List unlock = new ArrayList (); for (int i = 0; i ()); } for (int i = 0; i q = new LinkedList (); for (int i = 0; i subs = unlock.get(num); for (int i = 0; i subs.size(); i++) { int next = subs.get(i); preCount[next] -= 1; if (preCount[next] == 0) { q.offer(next); } } } return cnt == numCourses ?

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Python Queue在Pool的多进程中的共享方式 今天使用Pool使用Queue来传递数据的时候报错: Queue objects should only be shared between processes through inheritance 后来研究了一下发现网上的教程大部分是要求用mp包里的Manager来构建一个proxy来使用Queue,但其实解决这个错误不一定需要使用Manager.Queue,这个错误报错的地方其实是在fork的时候,把Queue对象作为参数传进给子进程导致的错误。所以使用

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pwr::pwr.t.test in R console ''' # 载入r对象 from rpy2 import robjects # 载入导入包函数 from rpy2.robjects.packages import importr # 将pwr包导入为模块,记得提前在(test环境下)R中安装好pwr包 pwr = importr('pwr') # When one wants to create a vector from Python, either the class Vector or the convenience classes IntVector, FloatVector, BoolVector, StrVector can be used. # 将参数中的.替换为_,解决不兼容问题, 来自rpy2文档

3分钟理解ES6箭头函数里的this

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mysql-5.7.17-linux-glibc2.5 的免编译安装

mysql-5.7.17-linux-glibc2.5 的免编译安装 1 ./bin/mysqld --user=mysql --basedir=/usr/local/mysql --datadir=/usr/local/mysql/data --initialize 2018-01-17T07:41:02.340159Z 0 [Warning] TIMESTAMP with implicit DEFAULT value is deprecated. Please use --explicit_defaults_for_timestamp server option (see documentation for more details).lGGrWng3qP 上面结果最后一个是mysql的初始密码。 9. 启动mysql .

Relationship Database Design

Relationship Database Design Content Conceptual model - ERD Logical model - schema, data dictionary, attributes mapping, ... A single line between Employee and its subclasses implies an optinal participation (an employee may not belong to any subclass), while a double line implies a mandatory participation (an employee must be in one or more subclasses). Meaning: the second and third normal forms normalize non-prime attributes, and BCNF normalizes relationships between prime attributes.

解读koa-compose

此时中间件三代码执行完毕,开始执行中间件二第二部分代码,执行完毕,开始执行中间一第二部分代码,执行完毕,所有中间件加载完毕。 总结 koa-compose 巧妙的运用了 compose 的特性,结合 async await 中 next 的等待执行,形成了洋葱模型,我们可以利用这一特性在 next 之前对 request 进行处理,而在 next 之后对 response 进行处理(例如 error 处理)

使用sftp在Ubuntu server上搭建ftp教程

message文件,可以用message_file来定义 xferlog_enable=YES #启用日志,默认路径/var/log/vsftpd.log connect_from_port_20=YES #数据连接使用默认的ftp-data端口(20端口) use_localtime=YES ssl_enable=NO local_root=/home/ftp cmds_denied=DELE,RMD #禁止删除 Use sudo service svftpd start to start the service