Tutorial by Examples: p

If you want the Value Types vs Reference Types in methods example to work properly, use the ref keyword in your method signature for the parameter you want to pass by reference, as well as when you call the method. public static void Main(string[] args) { ... DoubleNumber(ref number); ...

#include <stddef.h> // size_t, ptrdiff_t //----------------------------------- Machinery: using Size = ptrdiff_t; template< class Item, size_t n > constexpr auto n_items( Item (&)[n] ) noexcept -> Size { return n; } //----------------------------------- Us...

// Example of std::vector as an expanding dynamic size array. #include <algorithm> // std::sort #include <iostream> #include <vector> // std::vector using namespace std; int int_from( std::istream& in ) { int x = 0; in >> x; return x; } ...

This is useful to see if there are any non-printable characters, or non-ASCII characters. e.g. If you have copy-pasted the code from web, you may have quotes like ” instead of standard ". $ cat -v file.txt $ cat -vE file.txt # Useful in detecting trailing spaces. e.g. $ echo '” ' | c...

Because in .NET 3.5 and older you don't have Lazy<T> class you use the following pattern: public class Singleton { private Singleton() // prevents public instantiation { } public static Singleton Instance { get { return Nested.instanc...

To create a new Rails 5 API, open a terminal and run the following command: rails new app_name --api The following file structure will be created: create create README.rdoc create Rakefile create config.ru create .gitignore create Gemfile create app create app/as...

All collection objects contain a map method that takes a Function as an argument, which must take a single argument. This returns an Iterable backed by the collection. When the Iterable is iterated, each step calls the function with a new element of the collection, and the result of the call becomes...

You will often need to access instances of classes from the framework itself (like the WSClient, or the Configuration). You can inject them in your own classes : class ComplexService @Inject()( configuration: Configuration, wsClient: WSClient, applicationLifecycle: ApplicationLifecycle, ...

PBKDF2 ("Password-Based Key Derivation Function 2") is one of the recommended hash-functions for password-hashing. It is part of rfc-2898. .NET's Rfc2898DeriveBytes-Class is based upon HMACSHA1. using System.Security.Cryptography; ... public const int SALT_SIZE = 24; //...

mount is used to mount another application (basically rack application) or rails engines to be used within the current application syntax: mount SomeRackApp, at: "some_route" Now you can access above mounted application using route helper some_rack_app_path or some_rack_app_url. But ...

Step 1: Create the controller, set the delegate, and conform to the protocol //Swift class ImageUploadViewController: UIViewController, UIImagePickerControllerDelegate, UINavigationControllerDelegate { let imagePickerController = UIImagePickerController() override func viewDi...

Build numberDescription15.0.4623.1001June 201415.0.4631.1001July 201415.0.4641.1001August 201415.0.4649.1001September 201415.0.4659.1001October 201415.0.4667.1000November 201415.0.4675.1000December 201415.0.4693.1001February 201515.0.4701.1001March 201515.0.4711.1000April 2015 (SP1 REQ)15.0.4719.100...

LISP and Scheme's greatest advantage over other mainstream programming language is their macro system. Unlike the C preprocessor and other macro languages, Scheme macros take parsed code as input and return expanded code as output. This is one of the applications of Scheme's “code is data” phrase, a...

Converting an integer type to the corresponding promoted type is better than converting it to some other integer type. void f(int x); void f(short x); signed char c = 42; f(c); // calls f(int); promotion to int is better than conversion to short short s = 42; f(s); // calls f(short); exact mat...

To publish public repositories with a free npm account, you initially need to publish the module with access of public. One way to do this is to set the config for npm to read in packages.json as follows: "publishConfig": { "access": "public" }, you can also use...

The macro WITH-INPUT-FROM-STRING can be used to make a stream from a string. (with-input-from-string (str "Foobar") (loop for i from 0 for char = (read-char str nil nil) while char do (format t "~d: ~a~%" i char))) ; 0: F ; 1: o ; 2: o ; 3: b ;...

The macro WITH-OUTPUT-TO-STRING can be used to create a string output stream, and return the resulting string at the end. (with-output-to-string (str) (write-line "Foobar!" str) (write-string "Barfoo!" str)) ;=> "Foobar! ; Barfoo!" The same can be done ...

Method stopLoading() stops the current loading process of the webview. Swift webview.stopLoading() Objective-C [webview stopLoading];

There are three kinds of options: boolean options, string options, number options. To check the value of an option, use :set option? to check the value of an option, use :verbose set option? to also see where it was last set. Setting boolean options set booloption " Set boo...

Don't put comments after mappings, it will break things. Use :map <F6> to see what is mapped to <F6> and in which mode. Use :verbose map <F6> to also see where it was last mapped. :map and :map! are too generic. Use :n[nore]map for normal mode mappings, :i[nore]map for insert ...