Tutorial by Examples: d

const myArr = ['one', 'two', 'three'] const [ a, b, c ] = myArr // a = 'one', b = 'two, c = 'three' We can set default value in destructuring array, see the example of Default Value While Destructuring. With destructuring array, we can swap the values of 2 variables easily: var a = 1; var ...

Destructuring is a convenient way to extract properties from objects into variables. Basic syntax: let person = { name: 'Bob', age: 25 }; let { name, age } = person; // Is equivalent to let name = person.name; // 'Bob' let age = person.age; // 25 Destructuring and renaming: le...

Atom https://atom.io/packages/language-elm https://atom.io/packages/elmjutsu Light Table https://github.com/rundis/elm-light Sublime Text https://packagecontrol.io/packages/Elm%20Language%20Support Vim https://github.com/ElmCast/elm-vim Emacs https://github.com/jcollard/e...

The splice()method can be used to remove elements from an array. In this example, we remove the first 3 from the array. var values = [1, 2, 3, 4, 5, 3]; var i = values.indexOf(3); if (i >= 0) { values.splice(i, 1); } // [1, 2, 4, 5, 3] The splice() method can also be used to add elemen...

function foo() { console.trace('My log statement'); } foo(); Will display this in the console: My log statement VM696:1 foo @ VM696:1 (anonymous function) @ (program):1 Note: Where available it's also useful to know that the same stack trace is accessible a...

public static void Main() { var xml = new XmlDocument(); var root = xml.CreateElement("element"); // Creates an attribute, so the element will now be "<element attribute='value' />" root.SetAttribute("attribute", "value"); ...

In this example database for a library, we have Authors, Books and BooksAuthors tables. Live example: SQL fiddle Authors and Books are known as base tables, since they contain column definition and data for the actual entities in the relational model. BooksAuthors is known as the relationship tabl...

UDP is a connectionless protocol. Messages to other processes or computers are sent without establishing any sort of connection. There is no automatic confirmation if your message has been received. UDP is usually used in latency sensitive applications or in applications sending network wide broadca...

UDP is a connectionless protocol. This means that peers sending messages do not require establishing a connection before sending messages. socket.recvfromthus returns a tuple (msg [the message the socket received], addr [the address of the sender]) A UDP server using solely the socket module: from...

Sending data over the internet is made possible using multiple modules. The sockets module provides low-level access to the underlying Operating System operations responsible for sending or receiving data from other computers or processes. The following code sends the byte string b'Hello' to a TCP ...

The following will list up to ten of the most recently modified files in the current directory, using a long listing format (-l) and sorted by time (-t). ls -lt | head

NSString *filePath = [[NSFileManager defaultManager] pathForRessorce: @"data" ofType:@"txt"]; NSData *data = [NSData dataWithContentsOfFile:filePath]; int len = [data length];

NSDictionary *myDictionary = [[NSDictionary alloc] initWithObjectsAndKeys:@"value1", @"key1", @"value2", @"key2", nil]; NSArray *copiedArray = myDictionary.copy; Get keys: NSArray *keys = [myDictionary allKeys]; Get values: NSArray *values = [myDic...

NSDictionary *myDictionary = [[NSDictionary alloc] initWithObjectsAndKeys:@"value1", @"key1", @"value2", @"key2", nil]; NSData *myData = [NSKeyedArchiver archivedDataWithRootObject:myDictionary]; Reserve path: NSDictionary *myDictionary = (NSDictionary*...

NSDictionary *myDictionary = [[NSDictionary alloc] initWithObjectsAndKeys:@"value1", @"key1", @"value2", @"key2", nil]; NSMutableDictionary *mutableDictionary = [myDictionary mutableCopy]; NSData *data = [NSJSONSerialization dataWithJSONObject:myDiction...

Swift import SystemConfiguration /// Class helps to code reuse in handling internet network connections. class NetworkHelper { /** Verify if the device is connected to internet network. - returns: true if is connected to any internet network, false if is not co...

Although D3 is not specific for handling SVG elements, it is widely used for creating and manipulating complex SVG based data visualizations. D3 provides many powerful methods which helps to create various geometrical SVG structures with ease. It is recommended to understand basic concepts of SVG s...

\bfoo\b will match the complete word with no alphanumeric and _ preceding or following by it. Taking from regularexpression.info There are three different positions that qualify as word boundaries: Before the first character in the string, if the first character is a word character. After...

To generate true random values that can be used for cryptography std::random_device has to be used as generator. #include <iostream> #include <random> int main() { std::random_device crypto_random_generator; std::uniform_int_distribution<int> int_distribution(0,9); ...

A pseudo-random number generator generates values that can be guessed based on previously generated values. In other words: it is deterministic. Do not use a pseudo-random number generator in situations where a true random number is required. #include <iostream> #include <random> in...