Tutorial by Examples: e

If you want to use RSpec for a Rails project, you should use the rspec-rails gem, which can generate helpers and spec files for you automatically (for example, when you create models, resources or scaffolds using rails generate). Add rspec-rails to both the :development and :test groups in the Gem...

This is a copy of the advanced function snippet from the Powershell ISE. Basically this is a template for many of the things you can use with advanced functions in Powershell. Key points to note: get-help integration - the beginning of the function contains a comment block that is set up to be ...

To work with ConstraintLayout, you need Android Studio Version 2.2 or newer and have at least version 32 (or higher) of Android Support Repository. Add the Constraint Layout library as a dependency in your build.gradle file: dependencies { compile 'com.android.support.constraint:constraint...

Define your payload to send for possible more complex data $Payload = @{ text="test string"; username="testuser" } Use ConvertTo-Json cmdlet and Invoke-RestMethod to execute the call Invoke-RestMethod -Uri "https://hooks.slack.com/services/yourwebhookstring" -Metho...

For enabling Proguard configurations for your application you need to enable it in your module-level gradle file. You need to set the value of minifyEnabled to true. buildTypes { release { minifyEnabled true proguardFiles getDefaultProguardFile('proguard-android.t...

Example of calling an extension method as an extension and as a regular method. public Class MyClass Sub Main() 'Extension called directly on the object. Dim Version = Assembly.GetExecutingAssembly.GetVersionFromAssembly() 'Called as a regular method. ...

main.component.ts import {Component} from "@angular/core"; @Component({ selector: "main", template: ` <StackLayout> <TextField hint="some text"></TextField> <Button text="Click me" class="btn">...

Create a Dictionary<TKey, TValue> from an IEnumerable<T>: using System; using System.Collections.Generic; using System.Linq; public class Fruits { public int Id { get; set; } public string Name { get; set; } } var fruits = new[] { new Fruits { Id = 8 , Nam...

There are times when an include file has to generate different output from the preprocessor depending on whether the compiler is a C compiler or a C++ compiler due to language differences. For example a function or other external is defined in a C source file but is used in a C++ source file. Since...

A common problem in code that uses multidimensional arrays, arrays of pointers, etc. is the fact that Type** and Type[M][N] are fundamentally different types: #include <stdio.h> void print_strings(char **strings, size_t n) { size_t i; for (i = 0; i < n; i++) puts(str...

When allocating multidimensional arrays with malloc, calloc, and realloc, a common pattern is to allocate the inner arrays with multiple calls (even if the call only appears once, it may be in a loop): /* Could also be `int **` with malloc used to allocate outer array. */ int *array[4]; int i; ...

So far, we have looked at inserting a node at the beginning of a singly linked list. However, most of the times you will want to be able to insert nodes elsewhere as well. The code written below shows how it is possible to write an insert() function to insert nodes anywhere in the linked lists. #...

There's no built in way to search a list for a particular item. However Programming in Lua shows how you might build a set that can help: function Set (list) local set = {} for _, l in ipairs(list) do set[l] = true end return set end Then you can put your list in the Set and test for m...

Objective-C UIColor *color = [UIColor redColor]; NSString *textToFind = @"redword"; NSMutableAttributedString *attrsString = [[NSMutableAttributedString alloc] initWithAttributedString:yourLabel.attributedText]; // search for word occurrence NSRange range = [yourLabel.text rangeO...

<plugin> <groupId>org.apache.tomcat.maven</groupId> <artifactId>tomcat7-maven-plugin</artifactId> <version>2.1</version> <executions> <execution> <...

To be able to debug an application is very important to understand the flow of an application's logic and data. It helps solving logical bugs and adds value to the programming experience and code quality. Two popular gems for debugging are debugger (for ruby 1.9.2 and 1.9.3) and byebug (for ruby &g...

com.google.gson library needs to be added to use this code. Here is the example string: String companyDetails = {"companyName":"abcd","address":"abcdefg"} JSON strings can be parsed using below syntax in Java: JsonParser parser = new JsonParser(); Json...

PM2 lets you run your nodejs scripts forever. In the event that your application crashes, PM2 will also restart it for you. Install PM2 globally to manager your nodejs instances npm install pm2 -g Navigate to the directory in which your nodejs script resides and run the following command each t...

To start the process: $ forever start index.js warn: --minUptime not set. Defaulting to: 1000ms warn: --spinSleepTime not set. Your script will exit if it does not stay up for at least 1000ms info: Forever processing file: index.js List running Forever instances: $ forever list i...

In Python 2, True, False and None are built-in constants. Which means it's possible to reassign them. Python 2.x2.0 True, False = False, True True # False False # True You can't do this with None since Python 2.4. Python 2.x2.4 None = None # SyntaxError: cannot assign to None In ...