Tutorial by Examples: w

Destructuring allows you to extract data from various objects into distinct variables. In each example below, each variable is assigned to its own string (a="a", b="b", &c.) TypeExampleValue of data / commentvec(let [[a b c] data ...)["a" "b" "c&quot...

In the Project.pro file we add : CONFIG += sql in MainWindow.h we write : #include <QMainWindow> #include <QSql> #include <QDebug> namespace Ui { class MainWindow; } class MainWindow : public QMainWindow { Q_OBJECT public: explicit MainWindow(QWidget...

Method references make excellent self-documenting code, and using method references with Streams makes complicated processes simple to read and understand. Consider the following code: public interface Ordered { default int getOrder(){ return 0; } } public interface Valued&lt...

Given a file file.txt with the following content: line 1 line 2 line 3 You can add a new line using below command sed '/line 2/{x;p;x;}' file.txt The above command will output line 1 line 2 line 3 Explanation: x command is eXchange. sed has a buffer that you can use to store some ...

AWK often used for manipulating entire files containing a list of strings. Let's say file awk_test_file.txt contains: First String Second String Third String To convert all the strings to lower case execute: awk '{ print tolower($0) }' awk_test_file.txt This will result: first string se...

Show how to create simple converter with parameter via property and then pass it in declaration. Convert bool value to Visibility. Allow invert result value by setting Inverted property to True. public class BooleanToVisibilityConverter : IValueConverter { public bool Inverted { get; set; } ...

Show how to create simple converter and use ConverterParameter to pass parameter to converter. Multiply value by coefficient passed in ConverterParameter. public class MultiplyConverter : IValueConverter { public object Convert(object value, Type targetType, object parameter, CultureInfo cult...

If we want to get the x-cordinate of origin of the view, then we need to write like: view.frame.origin.x For width, we need to write: view.frame.size.width But if we add a simple extension to an UIView, we can get all the attributes very simply, like: view.x view.y view.width view.height...

$ read -r foo <<EOF > this is a line >EOF $ printf '%s\n' "$foo" this is a line

ALTER TABLE table_name ADD PARTITION new_partition VALUES LESS THAN(400);

Using some setters, without setting all needed properties in the constructor(s) public final class Person { // example of a bad immutability private final String name; private final String surname; public Person(String name) { this.name = name; } public String ge...

JasperSoft Studio If datasource or database connection is needed to fill report, create your Data Adapter in Repository Explorer by right clicking "Data Adapters" selecting "Create Data Adapter" Enter preview mode by selecting the Preview tab (no errors in deign need t...

The AND keyword is used to add more conditions to the query. NameAgeGenderSam18MJohn21MBob22MMary23F SELECT name FROM persons WHERE gender = 'M' AND age > 20; This will return: NameJohnBob using OR keyword SELECT name FROM persons WHERE gender = 'M' OR age < 20; This will return: n...

Magento custom module development is a core part of any Magento development or Magento project, because at any stage you may want to integrate your own functionality/module in your existing Magento project. The first thing developers should disable is the system cache. Otherwise developing will bec...

A string resource provides text strings for your application with optional text styling and formatting. There are three types of resources that can provide your application with strings: String XML resource that provides a single string. Syntax: <?xml version="1.0" encoding="...

Create a new project with the Leiningen figwheel template: lein new figwheel hello-world Run Figwheel: cd hello-world lein figwheel After a moment it will start a development webserver and open the page in your browser. It also opens a Clojurescript REPL connected to the browser. Try enter...

:s/foo/bar/c Marks the first instance of foo on the line and asks for confirmation for substitution with bar :%s/foo/bar/gc Marks consecutively every match of foo in the file and asks for confirmation for substitution with bar

try (Realm realm = Realm.getDefaultInstance()) { realm.executeTransaction(new Realm.Transaction() { @Override public void execute(Realm realm) { //whatever Transaction that has to be done } }); //No need to close realm in try-wit...

The Hello world example is as simple as: awk 'BEGIN {print "Hello world"}' The most basic awk program consists of a true value (typically 1) and makes awk echo its input: $ date | awk '1' Mon Jul 25 11:12:05 CEST 2016 Since "hello world" is also a true value, you could a...

async.waterfall(tasks, afterTasksCallback) will execute a set of tasks. Each task are executed after another, and the result of a task is passed to the next task. As async.series(), if a task fails, async stop the execution and call immediately the main callback. When tasks are finished successfull...