Tutorial by Examples: w

array_flip function will exchange all keys with its elements. $colors = array( 'one' => 'red', 'two' => 'blue', 'three' => 'yellow', ); array_flip($colors); //will output array( 'red' => 'one', 'blue' => 'two', 'yellow' => 'three' )

To change a text file is not easy because its content must be moved around. For small files easiest method is to read its content in memory and then write back modified text. In this example we read all lines from a file and drop all blank lines then we write back to original path: File.WriteAllLi...

This example updates last write time of a huge number of files (using System.IO.Directory.EnumerateFiles instead of System.IO.Directory.GetFiles()). Optionally you can specify a search pattern (default is "*.*" and eventually search through a directory tree (not only the specified director...

It's a good practice to run NodeJS apps controlled by process managers. Process manager helps to keep application alive forever, restart on failure, reload without downtime and simplifies administrating. Most powerful of them (like PM2) have a built-in load balancer. PM2 also enables you to manage ...

This simple example shows how to start multiple threads in Java. Note that the threads are not guaranteed to execute in order, and the execution ordering may vary for each run. public class HelloMultithreading { public static void main(String[] args) { for (int i = 0; i < 10; i...

cts:search( fn:doc(), cts:word-query("marklogic"))

This can be done in the following two ways - cts:search( fn:collection("first-collection"), cts:word-query("marklogic")) In this, the scope is changed from all the documents to documents in collection "first-collection" only. In the second approach, use ...

This query returns all the documents with element "company" and its value as "marklogic" cts:element-value-query(xs:QName('company'), 'marklogic'))

This example shows how to update a UI component from a background thread by using a SynchronizationContext void Button_Click(object sender, EventArgs args) { SynchronizationContext context = SynchronizationContext.Current; Task.Run(() => { for(int i = 0; i < 10; i++) ...

If you want to parse more complex command-line arguments, e.g. with optional parameters, than the best is to use google's GWT approach. All classes are public available at: https://gwt.googlesource.com/gwt/+/2.8.0-beta1/dev/core/src/com/google/gwt/util/tools/ToolBase.java An example for handling ...

The methods object.wait(), object.notify() and object.notifyAll() are meant to be used in a very specific way. (see http://stackoverflow.com/documentation/java/5409/wait-notify#t=20160811161648303307 ) The "Lost Notification" problem One common beginner mistake is to unconditionally cal...

// 1. Base example not using language support for covariance, dynamic type checking. class Top { public: virtual Top* clone() const = 0; virtual ~Top() = default; // Necessary for `delete` via Top*. }; class D : public Top { public: Top* clone() const override ...

The standard library module urllib.request can be used to download web content: from urllib.request import urlopen response = urlopen('http://stackoverflow.com/questions?sort=votes') data = response.read() # The received bytes should usually be decoded according the response's characte...

brew install zsh sudo echo '/usr/local/bin/zsh' >> /etc/shells chsh -s /usr/local/bin/zsh

Puppet is a configuration management solution. Users describe the desired state of a server or software and configuration management achieves this state. This brings following advantages: Configurations can be reproduced exactly the same every time, as many times as necessary Configurations for ...

You can create extension methods to improve usability for nested collections like a Dictionary with a List<T> value. Consider the following extension methods: public static class DictListExtensions { public static void Add<TKey, TValue, TCollection>(this Dictionary<TKey, TColl...

Usage of loops is an excellent way to keep the code DRY and avoid repetition. Unlike in Sass, there are no built-in @for or @each directive in Less for writing loops but it can still be written using recursive mixins. A recursive mixin is nothing but a mixin which keeps calling itself. There are fo...

private final Logger logger = Logger.getLogger(getClass().getCanonicalName()); WebView webView = new WebView(); webEngine = webView.getEngine(); webEngine.setOnAlert(event -> logger.warning(() -> "JS alert: " + event.getData()));

When using a WebView to display your own custom webpage and this webpage contains Javascript, it might be necessary to establish a two-way communication between the Java program and the Javascript in the web page. This example shows how to setup such a communication. The webpage shall display an i...

A for-each loop in Less has the same key components as a for loop except for the following differences: A variable which contains the list of items that has to be iterated over. An extract() function to extract each item in the variable based on the loop's index. A length() function to calculat...