Tutorial by Examples: di

Maps and keyword lists have different application. For instance, a map cannot have two keys with the same value and it's not ordered. Conversely, a Keyword list can be a little bit hard to use in pattern matching in some cases. Here's a few use cases for maps vs keyword lists. Use keyword lists wh...

One problem often seen in code is loading all the data. This will greatly increase the load on the server. Let's say I have a model called "location" that has 10 fields in it, but not all the fields are required at the same time. Let's say I only want the 'LocationName' parameter of that...

Let's take an example of a function which receives two arguments and returns a value indicating their sum: def two_sum(a, b): return a + b By looking at this code, one can not safely and without doubt indicate the type of the arguments for function two_sum. It works both when supplied with ...

Inline expansion can be disabled with the go:noinline pragma. For example, if we build the following simple program: package main func printhello() { println("Hello") } func main() { printhello() } we get output that looks like this (trimmed for readability): $ go ...

Occasionally, we may want to display dialogs with more than one pane of content. jQuery UI offers tabs that can be used in tandem with a dialog to make this possible. While it may be more common to have tabs within a dialog's content container, this example will demonstrate how to make a list of t...

Higher-order functions can be used to ensure that system resources are disposed, even when a treatment raises an exception. The pattern used by with_output_file allows a clean separation of concerns: the higher-order with_output_file functions takes care of managing the system resources bound to fi...

The ls command has several options that can be used together to show more information. Details/Rights The l option shows the file permissions, size, and last modified date. So if the root directory contained a dir called test and a file someFile the command: user@linux-computer:~$ ls -l Would ...

A type of dialog that contains an alert message, where initial focus goes to an element within the dialog. <div role="alertdialog"> <h1>Warning</h1> <div role="alert">Your session will expire in 60 seconds.</div> </div>

A dialog is an application window that is designed to interrupt the current processing of an application in order to prompt the user to enter information or require a response. <div role="dialog"> <p>Are you sure?</p> <button role="button">Yes</b...

A list of references to members of a group, such as a static table of contents. <ul role="directory"> <li><a href="/chapter-1">Chapter 1</a></li> <li><a href="/chapter-2">Chapter 2</a></li> <li><a ...

A heading for a section of the page. <h1 role="heading">Introduction</h1> <p>Lorem ipsum...</p>

A checkable menuitem in a group of menuitemradio roles, only one of which can be checked at a time. <ul role="menu"> <li role="menuitemradio" aria-checked="true">Left</li> <li role="menuitemradio" aria-checked="false">C...

A checkable input in a group of radio roles, only one of which can be checked at a time. <div role="radiogroup"> <input role="radio" type="radio" aria-checked="true"> One<br> <input role="radio" type="radio" aria...

A group of radio buttons. <div role="radiogroup"> <input role="radio" type="radio" aria-checked="true"> One<br> <input role="radio" type="radio" aria-checked="false"> Two<br> <input role=...

import java.io.BufferedReader; import java.io.BufferedWriter; import java.io.IOException; import java.nio.charset.StandardCharsets; import java.nio.file.Files; import java.nio.file.Paths; public class ReadingUTF8TextFile { public static void main(String[] args) throws IOException { ...

A simple context tree (containing some common values that might be request scoped and included in a context) built from Go code like the following: // Pseudo-Go ctx := context.WithValue( context.WithDeadline( context.WithValue(context.Background(), sidKey, sid), time.Now().A...

Assuming that you have successfully created a JFrame and that Swing has been imported... You can import Swing entirely import javax.Swing.*; or You can import the Swing Components/Frame that you intend to use import javax.Swing.Jframe; import javax.Swing.JButton; Now down to adding the J...

When reading from a file, we want to be able to know when we've reached the end of that file. Knowing that fgets() returns false at the end of the file, we might use this as the condition for a loop. However, if the data returned from the last read happens to be something that evaluates as boolean f...

To change MySQL's root user password: Step 1: Stop the MySQL server. in Ubuntu or Debian: sudo /etc/init.d/mysql stop in CentOS, Fedora or Red Hat Enterprise Linux: sudo /etc/init.d/mysqld stop Step 2: Start the MySQL server without the privilege system. sudo mysqld_safe --skip-grant-tab...

Using the Story Board: Select the tab bar item from the corresponding view controller and go to the attributes inspector If you want a built-in icon and title, set the 'System Item' to the corresponding value. For a custom icon, add the required images to the assets folder and set the 'System It...