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  Some tricks and tips for using for range in GoLang

GoLang provides two major ways to loop through elements of array, slice and map. They are for and for range. Many people find that for range is very convenient when don't care about the index of the element. In this post, some tricks and tips would be talked about regarding for range. 1. Loop and get pointer of each element Assume there is a code snippet like below which is to get the pointer of each element in an array and create a new array with the corresponding pointer. arr := [2]int{1, 2} r...

   POINTER,FOR LOOP,GOLANG,FOR RANGE     2020-03-08 01:07:00

  The Ultimate Guide to Implement Function Overloading in Python

Introduction When it comes to function overloading, those who have learned Java should be familiar with it. One of the most common uses is logging, where different overloaded functions are called for different parameters. So, how can we implement function overloading in Python? Concept of Overloading Function overloading allows multiple functions with the same name to exist within the same scope, but with different parameter lists. Although many programming languages (like Java and C++) support ...

   GUIDE,JAVA,OVERLOADING,PYTHON     2024-11-14 22:29:17

  A possible way to recover deleted files on Linux

Last week I was generating a MD5 sum for an virtual machine image on one OpenNebula server: # ls -l test.img -rw-r--r-- 1 root root 10486808576 Oct 12 02:21 test.img # md5sum test.img At the same time I was clearing the files on the server on another terminal and deleted the above image file mistakenly with : # rm test.img Since this image file is 10GB, it took some time to remove this file from the server, so I used the Ctrl+Z command to suspend the remove command. [1]+ Stopped ...

   Linux,File,Recovery     2013-11-26 07:03:37

  Mutli-inheritance bug between python 2.7 and 3.7

When we have run a py3.7 code under py2.x or a py2.x code under 3.x ,if a class do mutli-inheritance from 2 parent and the 2 parents also got inheritance from same parent, the different way to handle inheritance chain between python 2 and 3 will cause some running time bug: Assume we got this sample program inheritTest.py : # Purpose: Test mutli-inheritance different between python2 and 3 # Author: Yuancheng Liu # Created: 2019/05/16 class A: def getVal(self): print("cal...

   PYTHON,PYTHON 3,INHERITANCE     2019-05-16 08:33:52

  this in JavaScript in detail

this in JavaScript is always confusing, it is one of the most frequently seen traps in JavaScript. this is not a good design in JavaScript(You can refer some other design flaws of JavaScript here), since it's lazy binding feature, it can be a global object, the current object or.... Some people even avoid using this in JavaScript. Actually if you master how this works, then you will know how to stay away from these traps. Let's take a look at what this points to in below situations. 1. In global...

   JavaScript,this,bind     2013-05-09 18:35:12

  Binary tree iterator algorithm

Binary tree pre-order,in-order and post-order traversal are basics in algorithm and data structure.And the recursive binary tree traversal is a classical application of recursion. We define a binary tree node as : // C++ struct Node { int value; Node *left; Node *right; } In order binary tree traversal can be: // C++ void inorder_traverse(Node *node) { if (NULL != node->left) { inorder_traverse(node->left); } do_something(node); if (NULL != node->righ...

   Binary tree,Iterator,Traversal     2013-07-14 21:51:09

  Install Kubernetes with minikube and docker on Ubuntu

When someone just wants to play around Kubernetes on its local environment without accessing to Cloud provider resources, one can set Kubernetes up on local environment with minikube with single node mode. This post will provide a simple guideline on how to set up KUbernetes with minikube and docker on Ubuntu. Before all the steps can be started, you may need to first set up kubectl which is a command line tool to operate on Kubernetes resources. Post that, can ensure that docker is installed on...

   KUBERNETES,MINIKUBE,DOCKER,UBUNTU     2021-06-01 05:37:40

  SIEM Big Data Visualization : Dashboard for Monitoring Scam Events in Critical Infrastructure

Project Design Purpose: In a Security Information and Event Management (SIEM) system, effective monitoring and visualization of scam events is crucial to detecting and responding to cyberattacks. Cybercriminals often use deceptive methods to exploit individuals or organizations, aiming to steal sensitive information, financial assets, or disrupt operations. This project seeks to develop a web plugin dashboard to help cybersecurity researchers and managers better understand the scope and impact ...

       2024-10-05 20:47:09

  Turn on SecurityManager in Java

SecurityManager in Java is to check whether the application codes can access some restricted resource such as file, socket etc. This can be used in applications which have high security requirements. With this feature turned on, our system resources can be secured with only permitted operations. When JVM starts, it will first check whether the SecurityManager is on by checking the system property java.security.manager, if it's on, then an instance of SecurityManager will be created and it can be...

   SecurityManager,enable,program     2013-12-16 05:03:53

  New features in PHP 5.5

Just a few days ago, the PHP official website was redesigned. It seems we directly go from Web 1.0 era to Web 2.0 era. In addition to this new change, PHP 5.5 was also released. Some new features are added in this release. Here we summarize some of them. Enable OPCache by default When installing PHP 5.5, the Zend OPCache will be compiled as OPCache by default and OPCache is enabled by default. Some changes to the language itself Add Generator function getLinesFromFile($fileName) { if (!$file...

   PHP 5.5,New features,Generator     2013-07-05 03:13:22

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