Tutorial by Examples: d

We can use the unit type as a function argument to define functions that we don't want executed until later. This is often useful in asynchronous background tasks, when the main thread may want trigger some predefined functionality of the background thread, like maybe moving it to a new file, or if...

You can use conditional operators in WordPress to enqueue scripts on specific pages of your Website. function load_script_for_single_post(){ if(is_single()){ wp_enqueue_script( 'some', get_template_directory_uri().'/js/some.js', array...

Since vim version 7.3 the feature 'persistent_undo' is supported, which makes it possible do undo/redo changes, even after closing vim or restarting your computer. It's possible to configure it by adding the following to your vimrc, but first create a directory, where your undofiles should be saved...

Here's an example on how to use ACF to output differently based on options (color selections in this case). While you can use <?php echo get_field('color_options'); ?> to output the value directly, you can also change the markup depending on the selection. <?php $option = get_field('color_...

data table; set table; label variable1 = 'label1' variable2 = 'label2' variable3 = 'label3'; run;

Using SBT to manage the library dependency, add this to build.sbt: libraryDependencies += "org.scalactic" %% "scalactic" % "3.0.0" libraryDependencies += "org.scalatest" %% "scalatest" % "3.0.0" % "test" More details can be f...

import {User} from 'backend/user'; // import custom class import {inject} from 'aurelia-framework'; // allows us to inject @inject(User) // inject custom class export class ProfileView { constructor(user) { // use instance of custom class as a parameter to the constructor this.user = us...

add_option function ins used to insert new row into options table. This will insert a new row in options table with option name some_option_name and value as some_option_value <?php add_option( 'some_option_name', 'some_option_value' ); ?>

delete_option function is used to delete an option from the options table. This will delete my_custom_option from the options table. <?php delete_option( 'my_custom_option' ); ?>

update_option function is used to update a value that already exists in the options table. If the option does not exist, then the option will be added with the option value. This will set the default comment status to 'closed': update_option( 'default_comment_status', 'closed' );

The subprocess method that allows running commands needs the command in form of a list (at least using shell_mode=True). The rules to create the list are not always straightforward to follow, especially with complex commands. Fortunately, there is a very helpful tool that allows doing that: shlex. ...

Default WooCommerce checkout form comes with several fields for customers to enter their billing details. But in some cases, you might want to hide some of these fields. For example, if you are selling only virtual products, you can get rid of fields like billing address. Use the following code sn...

These functions will hash either String or Data input with one of eight cryptographic hash algorithms. The name parameter specifies the hash function name as a String Supported functions are MD2, MD4, MD5, SHA1, SHA224, SHA256, SHA384 and SHA512 This example requires Common Crypto It is nece...

These functions will hash either String or Data input with one of eight cryptographic hash algorithms. The name parameter specifies the hash function name as a String Supported functions are MD5, SHA1, SHA224, SHA256, SHA384 and SHA512 This example requires Common Crypto It is necessary to h...

Python allows you to hack list comprehensions to evaluate conditional expressions. For instance, [value_false, value_true][<conditional-test>] Example: >> n = 16 >> print [10, 20][n <= 15] 10 Here n<=15 returns False (which equates to 0 in Python). So what Python i...

SystemJS allows to write and use modular javacsript code that relies on ECMAScript 6 import and export statements. One good example is moment.js library, which started publishing ECMAScript 6 source code on npm since 2.10.0 release of moment.js. Installing prerequisites npm install moment npm ins...

var express = require('express'); var path = require('path'); var favicon = require('serve-favicon'); var app = express(); app.use(favicon(__dirname + '/public/img/favicon.ico')); app.use(express.static(path.join(__dirname, 'public'))); app.listen(3000, function() { console.log("...

var express = require('express'); var app = express(); var router = express.Router(); app.route('/user') .get(function (req, res) { res.send('Get a random user') }) .post(function (req, res) { res.send('Add a user') }) .put(function (req, res) { res.send...

The recommended approach would be to avoid doing so and rather use IOptions<TOptions> and IServiceCollection.Configure<TOptions>. That said, this is still pretty straightforward to make IConfigurationRootavailable application wide. In the Startup.cs constructor you should have the foll...

Install Java 8 from the Oracle website. (Optional) Install a Java build tool. Whether you choose to use Maven or Gradle, you normally don’t have to install anything, as JHipster will automatically install the Maven Wrapper or the Gradle Wrapper for you. If you don’t want to use those wrappers, ...