SEARCH KEYWORD -- Code snippet



  A small trick on using console.log to print data in JavaScript

When debugging JavaScript application, one may frequently use console.log to print data so that it is easy to debug when issue occurs and also helps on understand the data flow. The common way of printing a variable would be something like.  let user = { name: "test" }; console.log(user); In this case it will print: { name: 'test' } This is OK when there is no much logging or the program is not complicated. But it becomes difficult to debug if there are lots of variables to be printed ...

   JAVASCRIPT,CONSOLE.LOG,DEBUGGING     2019-09-03 10:24:24

  What is the use of empty struct in GoLang

In Go, an empty struct struct{} is a struct with no fields that may appear to be of little use, but in reality, it can be useful in certain situations and become a simple and efficient solution in code. As a semaphore or lock Because the empty struct has no fields, it can be conveniently used to implement some concurrency control functions, such as mutex locks, read-write locks. We can use chan struct{} to implement an unbuffered channel for controlling concurrent access. package main import ( ...

   GOLANG,EMPTY STRUCT     2024-04-05 23:54:03

  A simple tutorial about CSS flex property

CSS Flexbox is a layout module that makes it easier to create flexible and responsive layouts in CSS. It provides a simple and powerful way to align elements within a container and distribute space between them. To use flexbox, you need to set the display property of an element to "flex". You can do this by adding the following rule to your CSS: .container { display: flex; } The flex container will now have two main axes: the main axis and the cross axis. By default, the main axis runs horizo...

   JUSTIFY-CONTENT,FLEX,CSS     2022-12-25 06:44:34

  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

  Permutation implementation in Java

Permutation is a very basic and important mathematic concept we learned in school. It has very practical applications in real world. For example, in football. In simple, permutation describes all possible ways of doing something. For example, there are six permutations of the set {1,2,3}, namely: (1,2,3), (1,3,2), (2,1,3), (2,3,1), (3,1,2), and (3,2,1). In general, for n items, there are n! number of permutations to arrange these items. How can we implement this algorithm in programming programm...

   Permutation,Implementation,Java,Sample     2015-03-26 02:18:14

  A mini post on GoLang context

In a GoLang web server, every request coming in will be handled by a goroutine. In the request handler, the logic may also need to create new goroutine to handle other tasks like RPC call. When the request is processed and response is returned, these goroutines created need to be exited so that no goroutine leak should happen. package main import ( "fmt" "log" "net/http" ) func main() { http.HandleFunc("/echo", func(w http.ResponseWriter, r *http.Request) { fmt.Println(&r) w.Write(...

   CONTEXT,GOLANG     2019-12-14 06:21:02

  Why you should be careful about optimizations

In one of my current javascript projects, I have to deal with 3D voxel coordinates. And, sometimes, I have floating points coordinates which must be converted to integers in order to convert them into proper array index. Javascript is a wonderful language, really. However, implementations are sometimes weird, and the way to do something can sometimes have very huge impacts on the performances. Worse, sometimes the classical way is more expensive than the tricky one. So, some peo...

   JavaScript,Bitwise,Floor,Trick,Optimization     2012-05-02 11:29:20

  Introduction to GoLang generics and advanced usage

Generics in Go allow you to write code that can work with multiple types of data, without having to write separate versions of the code for each type. This can make your code more flexible and easier to maintain, as you only need to write and test the code once, rather than maintaining multiple versions. To use generics in Go, you first need to define a type parameter, which is a placeholder for the type that the code will work with. For example, you might define a type parameter called "T" like...

   GOLANG,GENERICS     2022-12-17 05:12:21

  Output a file with HTTP range header in PHP

When downloading a large file, we may encounter some network issues which causes download termination and only part of the file is downloaded. When the network connection resumes next time, we may need to redownload the file again from the beginning. In order to save bandwidth, http provides a Range parameter in its header which can control the file transfer flow. With the range parameter in the header, we can resume the download from where we stop. Here is a piece of PHP code snippet which uses...

   PHP, range,http, file transfer     2013-01-09 05:55:05

  How to check whether a struct implements an interface in GoLang

Unlike other programming languages like Java, when implementing an interface in GoLang, there is no syntax like below to explicit tell the relationship: type I interface { } type A struct implements I { } When looking at the code or running the code in GoLang, it might lead to a case one doesn't know whether a struct implements interface before trying to use it as some interface. According to GoLang spec, as long as a struct implements all functions of an interface, it is considered as having i...

   GOLANG,INTERFACE,IMPLEMENTATION,CHECK     2020-05-03 00:05:54