SEARCH KEYWORD -- SOURCE CODE


  errGroup in GoLang explained

Today, let's talk about the usage and applicable scenarios of errGroup, which is often used. Why is it useful? Generally, when we use goroutine, we cannot return a value. If you want to pass out the result of the goroutine execution, you usually have to use the channel. The errGroup package is suitable if you want to know when the goroutine you opened encounters an error during execution and stop working, and I need to know the error value. errGroup usage The package needs to be downloaded and i...

   GOLANG,ERRGROUP,WAITHROUP,CONCURRENCY     2023-05-27 23:58:20

  Create temp file in Bash using mktemp and trap

When working on Linux Bash, sometimes there is need to create temporary file. A common way of creating temp file on Linux is creating some file in /tmp directory. However there is security risk when creating temp file in /tmp directory. This post will show how to securely create temp file in Linux Bash. When creating file in /tmp directory, there are some security risks. This directory can be accessed by any user on the system, any user can write data into this directory as well. The files creat...

   LINUX,MKTEMP,TRAP,TEMP FILE     2019-12-30 23:28:23

  Be careful about printing error as string in GoLang

In GoLang, we can format and produce string using fmt.Printf(), just like C, GoLang also supports format verbs like %s, %d which can be placeholder for different types of values. But please pay attention when printing error as string so that you will not fall into some trap. Let's first take an example code snippet and see what trap we are talking about. package main import "fmt" type A string func (a A) Error() string { return fmt.Sprintf("%s is an error", a) } func main() { a := A("hello...

   STACKOVERFLOW,GOLANG,FMT     2019-01-23 09:17:15

  Write Your Own R Packages

Introduction A set of user-defined functions (UDF) or utility functions are helpful to simplify our code and avoid repeating the same typing for daily analysis work. Previously, I saved all my R functions to a single R file. Whenever I want to use them, I can simply source the R file to import all functions. This is a simple but not perfect approach, especially when I want to check the documentation of certain functions. It was quite annoying that you can’t just type ?func&n...

   DATA SCIENCE,R PROGRAMMING,DATA ENGINEERING     2019-10-19 07:20:52

  A trap about PHP random number

The method to get random number in PHP is very simple, we only need to use rand() function. int rand ( int $min , int $max ) One function call can return the random number in a specified range. But in fact, the random number in computer is actually pseudorandomness, generally to increase the randomness, we may set a random seed before calling rand(). void srand ([ int $seed ] ) According to other language features, we should pass a time value as a parameter to the srand() function, generally...

   PHP,rand,srand,mt_rand     2013-06-07 09:10:10

  Some frequently used ES6 code snippets

Below are a list of ES6 code snippets which are used frequently. Hope that it will be helpful. 1. Shuffle array elements let arr = [67, true, false, '55'] arr = arr.sort(() => 0.5 - Math.random()) console.log(arr) // [ '55', 67, false, true ] 2. Remove characters which are not numbers const str = 'xieyezi 23213 is 95994 so hansome 223333' const numbers = str.replace(/\D/g, '') console.log(numbers) // 2321395994223333 3. Reverse sequence or words const sentence = 'xieyezi js so handsome, lol.'...

   JAVASCRIPT,ES6,CODE SNIPPET,TIPS     2022-04-10 07:56:07

  5 tips for selling your software company for maximum value

From the moment you start your software company, you should be developing an exit strategy. While you might have no plans to sell your business, things can go wrong, and you can find yourself in a position with no other option. In this case, having a plan to go to will make the entire process easier. If you do plan on selling, you should be constantly improving your exit strategy as your business evolves in order to ensure you sell your company for maximum value. Selling a software company can ...

   TIPS,BUSINESS,SELLING,SOFTWARE BUSINESS     2017-11-14 03:44:52

  Where Have You Installed Your Python Packages?

Preface I am writing this article because I recently noticed in the Python community that there are several frequently asked questions: Why does running the command after installing pip result in a "executable not found" error? Why does importing a module result in a "ModuleNotFound" error? Why can I run my code in PyCharm, but it doesn't work in the command prompt? Rather than just providing solutions, it is better to teach people how to fish. To address these types of issues, you need to und...

   PYTHON,PATH,PATH_PREFIX,PACKAGE LOCATION     2023-12-17 01:03:45

  Social media sharing codes

Social media is becoming a very important traffic source to one website. We can see social media share buttons or links in most websites ranging from news website to personal blogs. It is also a very important optimization area where many SEO experts recommend. There are many social medias we can share our links to such as Facebook and Twitter. Most of these website provide share button for us to easily integrate them into our websites, but these buttons usually have default styles(fixed size, f...

   Social media,Share button,Cutomize     2013-07-18 23:12:45

  What do programmers like to say usually?

Coding is an very important part of programmer's daily work. But beyond coding, programmers need to do other work as well, they need to fix bugs reported by users, they need to write documents for their codes. Also, they often need to answer questions from customers, bosses and colleagues. What do they often say when they are facing different sort of questions? Today we share some. It's done. I just need to clean up a few things. This is hacky, but I'll fix it soon. This can never happen: It's ...

   Programmer,Execuse,Bug     2013-08-07 07:38:30

RECENT