Tutorial by Examples: le

Error handling is important but can make an elegant algorithm into a mess. Railway Oriented Programming (ROP) is used to make error handling elegant and composable. Consider the simple function f: let tryParse s = let b, v = System.Int32.TryParse s if b then Some v else None let f (g : ...
One of the great things about Linq is that it is so easy to extend. You just need to create an extension method whose argument is IEnumerable<T>. public namespace MyNamespace { public static class LinqExtensions { public static IEnumerable<List<T>> Batch<T&...
The following sqoop command will be used to import the data from RDBMS table into HBase table, if the table does not exists in HBase it will create a new table and import the data into this table sqoop import \ --query 'select emp_id, emp_name, emp_sal from employee where $CONDITIONS' \ ...
While-loops execute a body expression as long as the loop condition evaluates to true. A while-loop which logs numbers in range 9 to 0 (inclusive) can be written as follows: var i = 10; while (i-- > 0) { trace(i); } Try the example on try.haxe.org. References "While", Ha...
Do-while-loops execute a body expression at least once, and then keep executing it as long as the loop condition evaluates to true. A do-while-loop which logs numbers in range 10 to 0 (inclusive) can be written as follows: var i = 10; do { trace(i); } while (i-- > 0); Try the example ...
Anonymous class listener Before Java 8, it’s very common that an anonymous class is used to handle click event of a JButton, as shown in the following code. This example shows how to implement an anonymous listener within the scope of btn.addActionListener. JButton btn = new JButton("My Butto...
<style> input:in-range { border: 1px solid blue; } </style> <input type="number" min="10" max="20" value="15"> <p>The border for this value will be blue</p> The :in-range CSS pseudo-class matches when an element...
Singletons in Java are very similar to C#, being as both languages are object orientated. Below is an example of a singleton class, where only one version of the object can be alive during the program's lifetime (Assuming the program works on one thread) public class SingletonExample { priva...
To insert data retrieved from SQL query (single or multiple rows) INSERT INTO Table_name (FirstName, LastName, Position) SELECT FirstName, LastName, 'student' FROM Another_table_name Note, 'student' in SELECT is a string constant that will be inserted in each row. If required, you can select a...
using System; using System.Linq; using System.Security.Cryptography; namespace YourCryptoNamespace { /// <summary> /// Salted password hashing with PBKDF2-SHA1. /// Compatibility: .NET 3.0 and later. /// </summary> /// <remarks>See http://crackstation.net/h...
When a single parameter is passed to the .attr() function it returns the value of passed attribute on the selected element. Syntax: $([selector]).attr([attribute name]); Example: HTML: <a href="/home">Home</a> jQuery: $('a').attr('href'); Fetching data attributes: jQue...
(.) lets us compose two functions, feeding output of one as an input to the other: (f . g) x = f (g x) For example, if we want to square the successor of an input number, we can write ((^2) . succ) 1 -- 4 There is also (<<<) which is an alias to (.). So, (+ 1) <<&lt...
Control.Category defines (>>>), which, when specialized to functions, is -- (>>>) :: Category cat => cat a b -> cat b c -> cat a c -- (>>>) :: (->) a b -> (->) b c -> (->) a c -- (>>>) :: (a -> b) -> (b -> c) -> (a -> c...
In Insert mode, press <C-r> and then % to insert the filename. This technique is applicable to all registers. For e.g. if in insert mode, you want to paste the current search pattern, you can type <C-r> and then /.
While running any web application it’s necessary to take loading time into consideration. If your code tries to access any element that is not yet loaded, WebDriver will throw an exception and your script will stop. There are three types of Waits - Implicit Waits Explicit Waits Fluent Waits ...
In Racket, we use recursion very frequently. Here is an example of a function that sums all of the numbers from zero to the parameter, n. (define (sum n) (if (zero? n) 0 (+ n (sum (sub1 n))))) Note that there are many helpful convenience based functions used here, such as ...
The following example shows the declaration of a property (StringProperty in this case) and demonstrates how to add a ChangeListener to it. import java.text.MessageFormat; import javafx.beans.property.SimpleStringProperty; import javafx.beans.property.StringProperty; import javafx.beans.value.Ch...
This example shows how to use a readonly wrapper property to create a property that cannot be written to. In this case cost and price can be modified, but profit will always be price - cost. import java.text.MessageFormat; import javafx.beans.property.IntegerProperty; import javafx.beans.property...
Summary: MVVM is an architectural pattern that is represented by three distinct components, the Model, View and ViewModel. In order to understand these three layers, it is necessary to briefly define each, followed by an explanation of how they work together. Model is the layer that drives the bus...
The BubbleSort compares each successive pair of elements in an unordered list and inverts the elements if they are not in order. The following example illustrates the bubble sort on the list {6,5,3,1,8,7,2,4} (pairs that were compared in each step are encapsulated in '**'): {6,5,3,1,8,7,2,4} {**5...

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