Today's Question:  What does your personal desk look like?        GIVE A SHOUT

SEARCH KEYWORD -- METHOD PARAMETER

  What and what not to log while debugging

Log is a critical part of an application. It serves as an eye to the programmer on how the application is working while debugging. Especially for applications running on production environment, if the application encounters problem and the problem cannot be reproduced on other environments, log will be extremely useful. While log is essential, but developers have to log smartly. Because if don't put log smartly, you may not get what you want while debugging or you may get too many...

   PROGRAMMING,DEBUG,LOG,SUPPORT     2016-03-14 08:09:03

  Can a == true && a == false be true in JavaScript?

JavaScript is a weak typed language and it has a loose comparison feature where two objects/values of different type can be compared using == operator. This provides developers great flexibility and confusion at the same time.  Before understanding how == works in JavaScript, can you first answer the question in the post title? Can a == true && a == false be true in JavaScript? Normally, we would think that this expression will always return false since a can be either true or ...

   JAVASCRIPT,COMPARISON,INTERVIEW QUESTION,==     2018-03-25 03:39:43

  Common usage of ls command in Linux

In Linux, ls might be one of the most frequently used commands. It is used to list files in a specific directory. In most cases, we may just use ls -l to list the files under a directory. But have you explored other usages of this command. In this post, we will summarise some other common usages of ls command Assuming we have below directory structure in our system, let's see them using tree command. List details of the files If we want to list the details of the files in /home/alvin/test_...

   LINUX,SHELL,LS     2018-12-16 03:00:42

  What is Hystrix and How does Hystrix work

Background In distributed systems, there is one effect where the unavailability of one service or some services will lead to the service unavailability of the whole system, this is called service avalanche effect. A common way to prevent service avalanche is do manual service fallback, in fact Hystrix also provides another option beside this. Definition of Service Avalanche Effect Service avalanche effect is a kind of effect where the service provider fails to provide service which causes t...

   AVALANCHE EFFECT,HYSTRIX,DISTRIBUTED SYSTEM     2019-02-04 06:00:38

  JavaScript finite state machine

Finite state machine is a very useful design model, it can be used to simulate many events in the world. In short, finite state machine has three features: Number of states is finite At any moment, one object can only be in one state In some condition, it will transfer from one state to another state In JavaScript, finite state machine can be applied in many places. For example, one menu element on a webpage. When the mouse hovers on the menu, the menu will show up, while the mouse moves away...

   JavaScript,Finite state machine,State     2013-09-02 11:00:57

  Let's talk about JavaScript deep clone

In JavaScript, deep clone means creating a brand new object that includes all nested objects, with all properties being completely independent copies. This is different from shallow copying, which only copies the first-level properties, with nested objects being referenced rather than copied. There are multiple ways to perform deep copying in JavaScript, but the best one to use depends on the specific use case. Can use JSON.parse & JSON.stringify? ❌ JSON.parse(JSON.stringify(obj)) is a dep...

   JAVASCRIPT,DEEP CLONE     2023-02-25 08:57:11

  Guide to use Compass

Sass is one kind of CSS Preprocessor, it can make CSS development simple and maintainable. But to show its real power we may need to have Compass. This article is to introduce Compass. Once you learn Compass, your CSS development efficiency will be largely improved. Here we assume you have mastered the major uses of CSS, if you know Sass, then it's better. It's still ok if you don't know Sass. 1. What is Compass? In simple, Compass it the toolkit of Sass. Sass itself is only a compiler, Compass...

   Compass,CSS,Sass,Tutorial     2012-12-03 13:35:46

  How the Go language improves expressiveness without sacrificing runtime performance

This week there was a discussion on the golang-nuts mailing list about an idiomatic way to update a slice of structs. For example, consider this struct representing a set of counters. type E struct { A, B, C, D int } var e = make([]E, 1000) Updating these counters may take the form for i := range e { e[i].A += 1 e[i].B += 2 e[i].C += 3 e[i].D += 4 } Which is good idiomatic Go code. It's pretty fast too BenchmarkManual 500000 ...

   Go,Expressiveness,Performace,Sacrifice     2012-02-12 04:53:55

  Save QWidget as image

Qt library is an excellent GUI library for C++ programmers developed by Nokia and now is an open source project. Often, we may use QPainter to draw strings, lines or images on a QWidget. We can override the QWidget's paintEvent() method when we want to use QPianter object to draw something on a QWidget. If we want to save the items drawn on QWidget as image for later reference, what can we do? We can save a QWidget as an image. Here is the code for achieving this: QPixmap pixmap(this->size())...

   Qt,C++,QWidget,Image     2012-08-19 12:01:18

  Hide a file in a picture

Sometimes if you want to hide some important files on your computer which you don't want others to see, how would you do that? Find a professional tool? Set password for some folders? Change the file properties to hidden? They are possible, but they may not be so convenient or so secure. Here we share with you how to hide a file in a picture. Prerequisites 1 picture for example : test.jpg 1 test file, for example : test.txt WinRAR Steps Prepare the picture test.jpg and test file test.txt Use ...

   Trick,Picture,Fil hiding,WinRAR     2012-09-13 19:36:36

RECENT