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It is usually not a good idea to mix signed and unsigned integers in arithmetic operations. For example, what will be output of following example? #include <stdio.h> int main(void) { unsigned int a = 1000; signed int b = -1; if (a > b) puts("a is more than b&quot...

public bool IsTypeNullable<T>() { return Nullable.GetUnderlyingType( typeof(T) )!=null; }

A common usage scenario that this feature really helps with is when you are looking for an object in a collection and need to create a new one if it does not already exist. IEnumerable<MyClass> myList = GetMyList(); var item = myList.SingleOrDefault(x => x.Id == 2) ?? new MyClass { Id = 2...

This example shows how to use the default logging api. import java.util.logging.Level; import java.util.logging.Logger; public class MyClass { // retrieve the logger for the current class private static final Logger LOG = Logger.getLogger(MyClass.class.getName()); pub...

There are multiple ways to set a key's object in an NSDictionary, corresponding to the ways you get a value. For instance, to add a lamborghini to a list of cars Standard [cars setObject:lamborghini forKey:@"Lamborghini"]; Just like any other object, call the method of NSDictionary th...

There are multiple ways to get an object from an NSDictionary with a key. For instance, to get a lamborghini from a list of cars Standard Car * lamborghini = [cars objectForKey:@"Lamborghini"]; Just like any other object, call the method of NSDictionary that gives you an object for a ...

The simplest way to concatenate list1 and list2: merged = list1 + list2 zip returns a list of tuples, where the i-th tuple contains the i-th element from each of the argument sequences or iterables: alist = ['a1', 'a2', 'a3'] blist = ['b1', 'b2', 'b3'] for a, b in zip(alist, blist):...

from container to host docker cp CONTAINER_NAME:PATH_IN_CONTAINER PATH_IN_HOST from host to container docker cp PATH_IN_HOST CONTAINER_NAME:PATH_IN_CONTAINER If I use jess/transmission from https://hub.docker.com/r/jess/transmission/builds/bsn7eqxrkzrhxazcuytbmzp/ , the files in the contai...

Represents a thread-safe collection of key/value pairs that can be accessed by multiple threads concurrently. Creating an instance Creating an instance works pretty much the same way as with Dictionary<TKey, TValue>, e.g.: var dict = new ConcurrentDictionary<int, string>(); Ad...

Defining a method in Ruby 2.x returns a symbol representing the name: class Example puts def hello end end #=> :hello This allows for interesting metaprogramming techniques. For instance, methods can be wrapped by other methods: class Class def logged(name) original_method...

One of the more popular .NET providers for Postgresql is Npgsql, which is ADO.NET compatible and is used nearly identically as other .NET database providers. A typical query is performed by creating a command, binding parameters, and then executing the command. In C#: var connString = "Host=m...

You can use a For Each...Next loop to iterate through any IEnumerable type. This includes arrays, lists, and anything else that may be of type IEnumerable or returns an IEnumerable. An example of looping through a DataTable's Rows property would look like this: For Each row As DataRow In DataTable...

The following example shows how you can use Json.Net to serialize the data in an C# Object's instance, to JSON string. using System; using System.Collections.Generic; using Newtonsoft.Json; public class Employee { public string FirstName { get; set; } public string LastName { get; s...

The following example shows how you can deserialize a JSON string containing into an Object (i.e. into an instance of a class). using System; using System.Collections.Generic; using Newtonsoft.Json; public class Program { public class Employee { public s...

Bitwise operators can be used to perform bit level operation on variables. Below is a list of all six bitwise operators supported in C: SymbolOperator&bitwise AND|bitwise inclusive OR^bitwise exclusive OR (XOR)~bitwise not (one's complement)<<logical left shift>>logical right shift...

Dependencies npm i -D webpack babel-loader webpack.config.js const path = require('path'); module.exports = { entry: { app: ['babel-polyfill', './src/'], }, output: { path: __dirname, filename: './dist/[name].js', }, resolve: { extensions: ['', '.js'], }...

Required modules npm install --save-dev webpack extract-text-webpack-plugin file-loader css-loader style-loader Folder structure . └── assets    ├── css     ├── images    └── js webpack.config.js const webpack = require('webpack'); const ExtractTextPlugin = require('extract-text-webp...

Detailed instructions on getting database set up or installed.

In this example, we modify the "Simple class" example to allow access to the speed property. Typescript accessors allow us to add additional code in getters or setters. class Car { public position: number = 0; private _speed: number = 42; private _MAX_SPEED = 100 ...

If you want to import a module that doesn't already exist as a built-in module in the Python Standard Library nor as a side-package, you can do this by adding the path to the directory where your module is found to sys.path. This may be useful where multiple python environments exist on a host. im...