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Pi The following returns the value of PI formatted to 6 decimal places. The actual value is good to DOUBLE; SELECT PI(); -> 3.141593
public class ConnectSocketExample { private int HTTP_PORT = 80; /** * example method to create unconnected socket * then connect to it * at end return connected socket * * @param httpHostName - endpoint host name fot socket connection * @throws IOEx...
A macro is a series of keystrokes meant to be "played back" by Vim without any delay. Macros can be stored in registers or variables, bound to keys, or executed on the command line. Here is a simple macro that uppercases the third word on a line: 0wwgUiw That macro could be recorded i...
5.1 This Example demonstrates how to automatically assign a value to each entry in an enum list. This will prevent two enums from having the same value by mistake. NOTE: Object.freeze browser support var testEnum = function() { // Initializes the enumerations var enumList = [ &q...
A simple use case it to create an SKScene that exactly fills the SKView. This avoids the need to consider scaling the view to fit or setting a camera to show a part of the scene. The following code assumes an SKView called skView already exists (e.g. as defined in Create a Full Screen SKView using ...
An SKScene has a scaleMode parameter that defines how it will change its size to fit within the SKView it is presented into the SKView if it is not the same size and/or shape. There are four options for scaleMode: AspectFit: the scene is scaled (but not stretched) until it fits within the view. ...
You can place an SKCameraNode into an SKScene to define which part of the scene is shown in the SKView. Think of the SKScene as a 2D world with a camera floating above it: the SKView will show what the camera 'sees'. E.g. the camera could be attached to the main character's sprite to follow the act...
Chaining assignments as part of a var declaration will create global variables unintentionally. For example: (function foo() { var a = b = 0; })() console.log('a: ' + a); console.log('b: ' + b); Will result in: Uncaught ReferenceError: a is not defined 'b: 0' In the above examp...
The following function can be used to get some basic information about the current browser and return it in JSON format. function getBrowserInfo() { var json = "[{", /* The array containing the browser info */ info = [ navigator.userA...
After your service worker is registered, the browser will try to install & later activate the service worker. Install event listener this.addEventListener('install', function(event) { console.log('installed'); }); Caching One can use this install event returned to cache the assets ne...
FLOAT and DOUBLE represent approximate data types. TypeStoragePrecisionRangeFLOAT4 bytes23 significant bits / ~7 decimal digits10^+/-38DOUBLE8 bytes53 significant bits / ~16 decimal digits10^+/-308 REAL is a synonym for FLOAT. DOUBLE PRECISION is a synonym for DOUBLE. Although MySQL also permits...
WebSocket provides a duplex/bidirectional communication protocol over a single TCP connection. the client opens a connection to a server that is listening for a WebSocket request a client connects to a server using a URI. A server may listen to requests from multiple clients. Server Endpoint...
Character escaping is what allows certain characters (reserved by the regex engine for manipulating searches) to be literally searched for and found in the input string. Escaping depends on context, therefore this example does not cover string or delimiter escaping. Backslashes Saying that backsla...
Detailed instructions on excel-formula(s). There are many formulas that you can choose from. They are divided up into 7 different categories and are on the FORMULAS tab in Excel. The categories are: Financial Logical Text Date & Time Lookup & Reference Math & trig More Function...
You should not save props into state. It is considered an anti-pattern. For example: export default class MyComponent extends React.Component { constructor() { super(); this.state = { url: '' } this.onChange = this.onChange.bind(this); ...
Sometimes you doesn't want to simply replace or remove the string. Sometimes you want to extract and process matches. Here an example of how you manipulate matches. What is a match ? When a compatible substring is found for the entire regex in the string, the exec command produce a match. A match i...
Some regex engines (such as .NET) can handle context-free expressions, and will work it out. But that's not the case for most standard engines. And even if they do, you'll end up having a complex hard-to-read expression, whereas using a parsing library could make the job easier. How to find all p...
Because Regular Expressions can do a lot, it is tempting to use them for the simplest operations. But using a regex engine has a cost in memory and processor usage: you need to compile the expression, store the automaton in memory, initialize it and then feed it with the string to run it. And there...
UserType belongs to many Users <-> Users have one UserType One way navigation property with required public class UserType { public int UserTypeId {get; set;} } public class User { public int UserId {get; set;} public int UserTypeId {get; set;} public virtual UserType...
You can install Sinatra as a global gem: gem install sinatra or add it to a project's Gemfile # in Gemfile: gem 'sinatra' and run bundle install.

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