Tutorial by Examples: s

This is an extension of Basic Example: Basic Structure import React, { Component } from 'react'; import { render } from 'react-dom'; class FirstComponent extends Component { render() { return ( <div> Hello, {this.props.name}! I am a FirstCompon...

Executing code after 1.5 seconds: Handler handler = new Handler(); handler.postDelayed(new Runnable() { @Override public void run() { //The code you want to run after the time is up } }, 1500); //the time you want to delay in milliseconds Executing code repeatedly every...

It is possible to create a function that accepts objects that implement a specific trait. Static Dispatch fn generic_speak<T: Speak>(speaker: &T) { println!("{0}", speaker.speak()); } fn main() { let person = Person {}; let dog = Dog {}; generic_speak(...

An algorithmic problem is specified by describing the complete set of instances it must work on and of its output after running on one of these instances. This distinction, between a problem and an instance of a problem, is fundamental. The algorithmic problem known as sorting is defined as follows:...

__CLASS__ magic constant returns the same result as get_class() function called without parameters and they both return the name of the class where it was defined (i.e. where you wrote the function call/constant name ). In contrast, get_class($this) and get_called_class() functions call, will both ...

To switch between time zones, you need datetime objects that are timezone-aware. from datetime import datetime from dateutil import tz utc = tz.tzutc() local = tz.tzlocal() utc_now = datetime.utcnow() utc_now # Not timezone-aware. utc_now = utc_now.replace(tzinfo=utc) utc_now # Timezon...

int[] arr = new int[] { 0, 10, 20, 30}; // Get Console.WriteLine(arr[2]); // 20 // Set arr[2] = 100; // Get the updated value Console.WriteLine(arr[2]); // 100

Support for type hinting array parameters (and return values after PHP 7.1) was added in PHP 5.1 with the keyword array. Any arrays of any dimensions and types, as well as empty arrays, are valid values. Support for type hinting callables was added in PHP 5.4. Any value that is_callable() is valid ...

Since PHP objects don't inherit from any base class (including stdClass), there is no support for type hinting a generic object type. For example, the below will not work. <?php function doSomething(object $obj) { return $obj; } class ClassOne {} class ClassTwo {} $classOne= new...

Type hinting for classes and interfaces was added in PHP 5. Class type hint <?php class Student { public $name = 'Chris'; } class School { public $name = 'University of Edinburgh'; } function enroll(Student $student, School $school) { echo $student->name . ' is b...

const readline = require('readline'); const rl = readline.createInterface({ input: process.stdin, output: process.stdout }); rl.question('What is your name?', (name) => { console.log(`Hello ${name}!`); rl.close(); });

Objects will often depend on other objects. Instead of creating the dependency in the constructor, the dependency should be passed into the constructor as a parameter. This ensures there is not tight coupling between the objects, and enables changing the dependency upon class instantiation. This has...

Detailed instructions on getting spring-security set up or installed.

To remove an existing alias, use: unalias {alias_name} Example: # create an alias $ alias now='date' # preview the alias $ now Thu Jul 21 17:11:25 CEST 2016 # remove the alias $ unalias now # test if removed $ now -bash: now: command not found

Sometimes you may want to bypass an alias temporarily, without disabling it. To work with a concrete example, consider this alias: alias ls='ls --color=auto' And let's say you want to use the ls command without disabling the alias. You have several options: Use the command builtin: command...

Note: GRAILS requires a Java JDK installed (a runtime environment JRE is not sufficient) on your system, before setting up Grails. Please refer to, how to install JDK. As of this writing, it is recommended to install the latest JDK. For Mac OSX, Linux, Cygwin, Solaris and FreeBSD: The simplest w...

[alias] logp=log --pretty=format:'%h %ad | %s%d [%an]' --graph --date=short lg = log --graph --date-order --first-parent \ --pretty=format:'%C(auto)%h%Creset %C(auto)%d%Creset %s %C(green)(%ad) %C(bold cyan)<%an>%Creset' lgb = log --graph --date-order --branches --first-paren...

Adding the DebuggerDisplay Attribute will change the way the debugger displays the class when it is hovered over. Expressions that are wrapped in {} will be evaluated by the debugger. This can be a simple property like in the following sample or more complex logic. [DebuggerDisplay("{StringPr...

There are multiple threads in your code and you need to safely communicate between them. You can use a Queue from the queue library. from queue import Queue from threading import Thread # create a data producer def producer(output_queue): while True: data = data_computation() ...

In Objective-C, method swizzling is the process of changing the implementation of an existing selector. This is possible due to the way Selectors are mapped on a dispatch table, or a table of pointers to functions or methods. Pure Swift methods are not dynamically dispatched by the Objective-C run...