Tutorial by Examples: n

std::ifstream src("source_filename", std::ios::binary); std::ofstream dst("dest_filename", std::ios::binary); dst << src.rdbuf(); C++17 With C++17 the standard way to copy a file is including the <filesystem> header and using copy_file: std::fileystem::copy...

The first thing you need to do is create a connection to the database using the connect method. After that, you will need a cursor that will operate with that connection. Use the execute method of the cursor to interact with the database, and every once in a while, commit the changes using the comm...

Sometimes you may want to have local changes in a file you don't want to commit or publish. Ideally local settings should be concentrated in a separate file that can be placed into .gitignore, but sometimes as a short-term solution it can be helpful to have something local in a checked-in file. You...

.gitignore and .git/info/exclude work only for untracked files. To set ignore flag on a tracked file, use the command update-index: git update-index --skip-worktree myfile.c To revert this, use: git update-index --no-skip-worktree myfile.c You can add this snippet to your global git config ...

namespace CodeContractsDemo { using System; using System.Collections.Generic; using System.Diagnostics.Contracts; public class PaymentProcessor { private List<Payment> _payments = new List<Payment>(); public void Add(Payment payment) ...

public double GetPaymentsTotal(string name) { Contract.Ensures(Contract.Result<double>() >= 0); double total = 0.0; foreach (var payment in this._payments) { if (string.Equals(payment.Name, name)) { total += payment.Amount; } } ...

namespace CodeContractsDemo { using System; using System.Diagnostics.Contracts; public class Point { public int X { get; set; } public int Y { get; set; } public Point() { } public Point(int x, int y) { ...

[ContractClass(typeof(ValidationContract))] interface IValidation { string CustomerID{get;set;} string Password{get;set;} } [ContractClassFor(typeof(IValidation))] sealed class ValidationContract:IValidation { string IValidation.CustomerID { [Pure] get ...

A common use-case for iterators is to perform some operation over a collection of numbers. The example below demonstrates how each element within an array of numbers can be individually printed out to the console. This is possible because arrays implement the IEnumerable interface, allowing clients...

Swift let isPushEnabled = UIApplication.sharedApplication().isRegisteredForRemoteNotifications()

The logic of registering for push notification is recommended to be added in AppDelegate.swift as the callback functions (success, failure) will be called their. To register just do the following: let application = UIApplication.sharedApplication() let settings = UIUserNotificationSettings(forType...

Once user clicks on a push notification, the following callback function will be called. You can parse the JSON to get any specific info sent from backend that will helps you in deep linking: Swift func application(application: UIApplication, didReceiveRemoteNotification userInfo: [NSObject : ...

Assume you want to create an extension property that is expensive to compute. Thus you would like to cache the computation, by using the lazy property delegate and refer to current instance (this), but you cannot do it, as explained in the Kotlin issues KT-9686 and KT-13053. However, there is an off...

cURL is the name of the project which depicts: 'Client for URLs' and also be called as Client URL Request Library it combines two separate packages: curl and libcurl. curl is a command line tool used to get documents/files from or send documents to a server, using any of the supported protocol...

Python 2.x2.3 python -m SimpleHTTPServer 9000 Python 3.x3.0 python -m http.server 9000 Running this command serves the files of the current directory at port 9000. If no argument is provided as port number then server will run on default port 8000. The -m flag will search sys.path for ...

A stream is closed by sending a closing </stream> tag. After the closing stream tag is sent, no more data should be sent on the stream (even in response to data received from the other party). Before closing the connection, the sending entity should wait for a response </stream> tag to g...

Once a TCP connection is established, the initial stream header is sent by the initiating entity. Similarly, whenever a stream restart is required (eg. after negotiating a security layer such as TLS) a stream header must also be sent: <?xml version='1.0'?> <stream:stream from='juliet...

Mixins are a beautiful way to achieve something similar to multiple inheritance. It allows us to inherit or rather include methods defined in a module into a class. These methods can be included as either instance or class methods. The below example depicts this design. module SampleModule def...

The WHILE loop can be used as an alternative to CURSORS. The following example will print numbers from 0 to 99. DECLARE @i int = 0; WHILE(@i < 100) BEGIN PRINT @i; SET @i = @i+1 END

dplyr::filter() - Select a subset of rows in a data frame that meet a logical criteria: dplyr::filter(iris,Sepal.Length>7) # Sepal.Length Sepal.Width Petal.Length Petal.Width Species # 1 7.1 3.0 5.9 2.1 virginica # 2 7.6 3.0 ...