Tutorial by Examples: u

// Animal.php class Animal { public function eats($food) { echo "Yum, $food!"; } } // zoo.php require 'Animal.php'; $animal = new Animal; $animal->eats('slop'); // aquarium.php require 'Animal.php'; $animal = new Animal; $animal->eats('shrimp'); H...

// autoload.php spl_autoload_register(function ($class) { require_once "$class.php"; }); // Animal.php class Animal { public function eats($food) { echo "Yum, $food!"; } } // zoo.php require 'autoload.php'; $animal = new Animal; $animal->e...

// autoload.php spl_autoload_register(function ($class) { require_once "$class.php"; }); // Animal.php class Animal { public function eats($food) { echo "Yum, $food!"; } } // Ruminant.php class Ruminant extends Animal { public function eat...

It is possible to create an anonymous struct: data := struct { Number int Text string } { 42, "Hello world!", } Full example: package main import ( "fmt" ) func main() { data := struct {Number int; Text string}{42, "Hello worl...

A singleton is a pattern that restricts the instantiation of a class to one instance/object. For more info on python singleton design patterns, see here. class SingletonType(type): def __call__(cls, *args, **kwargs): try: return cls.__instance except AttributeErr...

An unordered list can be created with the <ul> tag and each list item can be created with the <li> tag as shown by the example below: <ul> <li>Item</li> <li>Another Item</li> <li>Yet Another Item</li> </ul> This will produce a...

Right after you install Git, the first thing you should do is set your username and email address. From a shell, type: git config --global user.name "Mr. Bean" git config --global user.email [email protected] git config is the command to get or set options --global means that the ...

$ tail -f /var/log/syslog > log.txt [1]+ Stopped tail -f /var/log/syslog > log.txt $ sleep 10 & $ jobs [1]+ Stopped tail -f /var/log/syslog > log.txt [2]- Running sleep 10 &

The function rand() can be used to generate a pseudo-random integer value between 0 and RAND_MAX (0 and RAND_MAX included). srand(int) is used to seed the pseudo-random number generator. Each time rand() is seeded wih the same seed, it must produce the same sequence of values. It should only be see...

Here's a standalone random number generator that doesn't rely on rand() or similar library functions. Why would you want such a thing? Maybe you don't trust your platform's builtin random number generator, or maybe you want a reproducible source of randomness independent of any particular library ...

> redirect the standard output (aka STDOUT) of the current command into a file or another descriptor. These examples write the output of the ls command into the file file.txt ls >file.txt > file.txt ls The target file is created if it doesn't exists, otherwise this file is truncated. ...

File descriptors like 0 and 1 are pointers. We change what file descriptors point to with redirection. >/dev/null means 1 points to /dev/null. First we point 1 (STDOUT) to /dev/null then point 2 (STDERR) to whatever 1 points to. # STDERR is redirect to STDOUT: redirected to /dev/null, # effect...

Truncate > Create specified file if it does not exist. Truncate (remove file's content) Write to file $ echo "first line" > /tmp/lines $ echo "second line" > /tmp/lines $ cat /tmp/lines second line Append >> Create specified file if it does not e...

Browse to File > New > Solution to bring you up the new project dialog Select Single View App and press Next Configure your app by setting your app name and organization ID, and press Next: Set your Project name and Solution name, or leave as the default name. Click Create to create...

A simple two-column layout consists of two fixed-width, floated elements. Note that the sidebar and content area are not the same height in this example. This is one of the tricky parts with multi-column layouts using floats, and requires workarounds to make multiple columns appear to be the same he...

Events fired on DOM elements don't just affect the element they're targeting. Any of the target's ancestors in the DOM may also have a chance to react to the event. Consider the following document: <!DOCTYPE html> <html> <head> <meta charset="utf-8" /> </hea...

This downloads a file from the Dropbox API at the remote path /Homework/math/Prime_Numbers.txt to the local path Prime_Numbers.txt in the current folder: curl -X POST https://content.dropboxapi.com/2/files/download \ --header "Authorization: Bearer <ACCESS_TOKEN>" \ --head...

Adapted from the tutorial, this uses the SwiftyDropbox library to download a file, with a progress callback on the download method to get progress information: // Download a file let destination : (NSURL, NSHTTPURLResponse) -> NSURL = { temporaryURL, response in let fileManager = NSFileMan...

This uses the Dropbox Python SDK to download a file from the Dropbox API at the remote path /Homework/math/Prime_Numbers.txt to the local file Prime_Numbers.txt: import dropbox dbx = dropbox.Dropbox("<ACCESS_TOKEN>") with open("Prime_Numbers.txt", "wb") as f:...

Dropbox.authorizedClient!.files.download(path: path, destination: destination).response { response, error in if let (metadata, url) = response { print("*** Download file ***") print("Downloaded file name: \(metadata.name)") print("Downloaded f...