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  Removing all child nodes from an element

When manipulating the DOM, it's often useful to remove all child nodes from a specific element. This typically comes in handy when you're looking to replace the content of an element with a separate form element, such as an <input>, so the user can edit the actual value.Here's an example of something I recently created that illustrates my point:Get the Flash Player to see this player.These "dynamic form elements" are written to the page only when the...

   Js,DOM,Remove all children,Clear,JavaScript,Code     2011-10-19 10:04:23

  The evolving history of asynchronous operation in JavaScript

JavaScript is single threaded, it means there would be only one task running at any point of time. But this would slow down the overall program execution if there is long running task, hence asynchronous task execution is desired in complex cases. To achieve asynchronous task execution, there are a few options introduced in JavaScript. setTimeout/setInterval Event Promise Async/Await setTimeout/setInterval is one of the first mechanisms introduced in JavaScript to simulate asynchronous operati...

   JAVASCRIPT,ASYNC,PROMISE,AWAIT     2019-11-09 08:21:56

  On Erlang's Syntax

I first planned to release this text as an appendix entry for Learn You Some Erlang, but considering this feels more like editorial content and not exactly something for a reference text, I decided it would fit better as a blog post. Many newcomers to Erlang manage to understand the syntax and program around it without ever getting used to it. I've read and heard many complaints regarding the syntax and the 'ant turd tokens' (a subjectively funny way to refer to ,, ; and .), how annoying...

   Erlang,Syntax,Error     2011-12-22 08:35:42

  Native Client Brings Sandboxed Native Code to Chrome Web Store Apps

Wouldn’t it be great if you could create web apps using your existing C and C++ code? Native Client lets you do just that, and it is now enabled for Chrome Web Store apps in Google Chrome’s beta channel. Native Client apps live on the web platform, so you don’t need to create separate versions of your app for each operating system. Rather than relying on OS-specific APIs, Native Client apps use Pepper, a set of interfaces that provide C and C++ bindings to the capabilities o...

   C++,Web application,Native Client,Useful     2011-08-24 02:23:03

  A C++ program puzzle

Recently I came across a question asked by wang2191195 on a Chinese IT forum CSDN which asks about a C++ program puzzle. He has a code snippet which cannot be compiled. The code is:#include <cstdlib> #include <iostream> using namespace std; class Base{ public: virtual void func(){ cout << "Base::func()" << endl; } virtual int func( int num ){ cout << "Base::func( int " << num << " )" << endl; return 0; ...

   C++,Puzzle,Hide,Overload     2012-05-13 02:31:26

  passing parameters to XMLHttpRequest’s onreadystatechange function

I’ve been smashing my head against this all day – but I finally got something working consistently and reliable, so I better damn well document it. This is as good a place as any, and hopefully it will be useful to others.I needed to make an Ajax call, so I turned to my good friend XMLHttpRequest. One wrinkle was that I needed to pass in a parameter to it… so I tried:var test = "bar"; req = new XMLHttpRequest(); req.open("GET", myURL, true); req.foo = test; req.onreadystatech...

   JavaScript,AJAX,XMLHttpRequest,parameter,onreadystatechange     2011-10-09 01:32:09

  C Preprocessor Hell

Lisp programmers should stop reading right now because they'll likely suffer severe injury of the jaw muscles as they laugh themselves silly at how hard it is to do some things in C. The C language has a pre-processor (typically called cpp) that is both infuriating and powerful. How powerful is usually best described as 'just too little' and it has happened more than once that I found myself almost - but not quite - able to do what I wanted to do. The frustration can run very deep at ti...

   C,Preprocessor,Lisp,Hell     2012-01-19 10:22:31

  How Query Optimizer Works in RDBMS

In a previous post, we discussed how the various relational operators are implemented in relational database systems. If you have read that post, you probably still remember that there are a few alternative implementations for every operator. Thus, how should RDBMS determine which algorithm (or implementation) to use? Obviously, to optimize the performance for any query, RDBMS has to select the correct the algorithm based on the query. It would not be desirable to always use the same algori...

   DATABASE,DATABASE DESIGN,DATABASE OPTIMIZATION     2019-04-20 07:26:32

  Remove duplicated elements in JavaScript array

During interviews, one frequent question asked would be something like how to remove duplicated elements in a JavaScript array and how many different ways you can think of. The interviewee would also be asked to write the code down. In real applications, normally front end would not need to handle this case since normally it would be done by backend, but still it's necessary for front end developers to know different ways of doing this. This post will share some of the common ways to remove dupl...

   JAVASCRIPT,ARRAY,DUPLICATED ELEMENT     2018-09-21 22:32:10

  JSON unmarshal in GoLang

In almost all mainstream programming languages, there is either built-in or third-party library to support parse JSON data because it is so popular for organizing and transferring data among different services. In GoLang, the built in json package also provides functions for marshalling and unmarshalling JSON data. Marshalling GoLang struct to a JSON string is relatively simple, just need to call json.Marshal(), it's a bit complicated to unmarshal an arbitrary JSON string into a GoLang struct ob...

   GOLANG,JSON,UNMARSHAL,EMPTY INTERFACE     2019-11-09 21:57:30

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