Tutorial by Examples: g

In PHP, a fatal error is a kind of error that cannot be caught, that is, after experiencing a fatal error a program does not resume. However, to log this error or somehow handle the crash you can use register_shutdown_function to register shutdown handler. function fatalErrorHandler() { // Let...

Whenever you attempt to retrieve a certain field from a class like so: $animal = new Animal(); $height = $animal->height; PHP invokes the magic method __get($name), with $name equal to "height" in this case. Writing to a class field like so: $animal->height = 10; Will invoke...

A binary is a sequence of unsigned 8-bit bytes. 1> <<1,2,3,255>>. <<1,2,3,255>> 2> <<256,257,258>>. <<0,1,2>> 3> <<"hello","world">>. <<"helloworld">> A bitstring is a generalized ...

Migrations in a Laravel 5 application live in the database/migrations directory. Their filenames conform to a particular format: <year>_<month>_<day>_<hour><minute><second>_<name>.php One migration file should represent a schema update to solve a particu...

Creating a new migration file with the correct filename every time you need to change your schema would be a chore. Thankfully, Laravel's artisan command can generate the migration for you: php artisan make:migration add_last_logged_in_to_users_table You can also use the --table and --create fla...

Each migration should have an up() method and a down() method. The purpose of the up() method is to perform the required operations to put the database schema in its new state, and the purpose of the down() method is to reverse any operations performed by the up() method. Ensuring that the down() me...

Once your migration is written, running it will apply the operations to your database. php artisan migrate If all went well, you'll see an output similar to the below: Migrated: 2016_07_21_134310_add_last_logged_in_to_users_table Laravel is clever enough to know when you're running migration...

The following code creates a simple user interface containing a single Button that prints a String to the console on click. import javafx.application.Application; import javafx.scene.Scene; import javafx.scene.control.Alert; import javafx.scene.control.Alert.AlertType; import javafx.scene.contr...

We are going to be showing how to make a GET request to an API that responds with a JSON object or a JSON array. The first thing we need to do is add the Retrofit and GSON Converter dependencies to our module's gradle file. Add the dependencies for retrofit library as described in the Remarks secti...

Run-length encoding captures the lengths of runs of consecutive elements in a vector. Consider an example vector: dat <- c(1, 2, 2, 2, 3, 1, 4, 4, 1, 1) The rle function extracts each run and its length: r <- rle(dat) r # Run Length Encoding # lengths: int [1:6] 1 3 1 1 2 2 # valu...

One of the first questions people have when they begin to use PowerShell for scripting is how to manipulate the output from a cmdlet to perform another action. The pipeline symbol | is used at the end of a cmdlet to take the data it exports and feed it to the next cmdlet. A simple example is using...

Ansible maintains a PPA repository that can be used to install the Ansible binaries: sudo apt-add-repository ppa:ansible/ansible -y sudo apt-get update && sudo apt-get install ansible -y To install a specific version, use pip. The PPA may be out of date.

There are two main ways way to install Ansible on OS X, either using the Homebrew or Pip package manager. If you have homebrew, the latest Ansible can be installed using the following command: brew install ansible To install Ansible 1.9.X branch use following command: brew install homebrew/ver...

CSS div { height: 100px; width: 100px; border: 1px solid; transition-property: height, width; transition-duration: 1s, 500ms; transition-timing-function: linear; transition-delay: 0s, 1s; } div:hover { height: 200px; width: 200px; } HTML <div></div> ...

The virtualenvwrapper utility simplifies working with virtual environments and is especially useful if you are dealing with many virtual environments/projects. Instead of having to deal with the virtual environment directories yourself, virtualenvwrapper manages them for you, by storing all virtual...

The OR (||) operator returns true if one of its two operands evaluates to true, otherwise it returns false. For example, the following code evaluates to true because at least one of the expressions either side of the OR operator is true: if (10 < 20) || (20 < 10) { print("Expression...

type person = {Name: string; Age: int} // Defines person record let user1 = {Name = "John Doe"; Age = 27} // creates a new person let user2 = {user1 with Age = 28} // creates a copy, with different Age let user3 = {user1 with Name = "Jane Doe"; Age = 29} //creates ...

Similar to rgb() notation, but with an additional alpha (opacity) value. .red { /* Opaque red */ color: rgba(255, 0, 0, 1); } .red-50p { /* Half-translucent red. */ color: rgba(255, 0, 0, .5); } Syntax rgba(<red>, <green>, <blue>, <alpha>); Va...

For setting some zoom level, let say we want to zoom user's location with user location as center and 2km of area as radius. Then, we use following code MKUserLocation *userLocation = _mapView.userLocation; MKCoordinateRegion region = MKCoordinateRegionMakeWithDistance (userLocation.location.coord...

MKLocalSearch allows users to search for location using natural language strings like "gym". Once the search get completed, the class returns a list of locations within a specified region that match the search string. Search results are in form of MKMapItem within MKLocalSearchResponse ob...