Tutorial by Examples: le

// Store a reference to the native method let open = XMLHttpRequest.prototype.open; // Overwrite the native method XMLHttpRequest.prototype.open = function() { // Assign an event listener this.addEventListener("load", event => console.log(XHR), false); // Call the s...

Files: To determine if a file exists, simply pass the filename to the Dir$ function and test to see if it returns a result. Note that Dir$ supports wild-cards, so to test for a specific file, the passed pathName should to be tested to ensure that it does not contain them. The sample below raises an...

NOTE: For brevity, the examples below use the FolderExists function from the Determining If Folders and Files Exist example in this topic. The MkDir statement can be used to create a new folder. It accepts paths containing drive letters (C:\Foo), UNC names (\\Server\Foo), relative paths (..\Foo...

As the picture aspect ratio example indicates, videos are series of pictures that do not necessarily have the same aspect ratio as the final result to be displayed to the user. So how do you get from those stretched pictures to the normally displayed output? You need a stretching factor! This stret...

Consider the following list comprehension Python 2.x2.7 i = 0 a = [i for i in range(3)] print(i) # Outputs 2 This occurs only in Python 2 due to the fact that the list comprehension “leaks” the loop control variable into the surrounding scope (source). This behavior can lead to hard-to-find...

To create a Behavior just extend the CoordinatorLayout.Behavior class. Extend the CoordinatorLayout.Behavior Example: public class MyBehavior<V extends View> extends CoordinatorLayout.Behavior<V> { /** * Default constructor. */ public MyBehavior() { ...

One application of closures is to partially apply a function; that is, provide some arguments now and create a function that takes the remaining arguments. Currying is a specific form of partial application. Let's start with the simple function curry(f, x) that will provide the first argument to a ...

Theorem my_first_theorem : 1 + 1 = 2. Proof. reflexivity. Qed. Try it in your browser.

Profiles permit the programmer to organize maps into classes, enhancing code readability and maintainability. Any number of profiles can be created, and added to one or more configurations as needed. Profiles can be used with both the static and instance-based APIs. public class User { public...

Often it is useful to be able to load all of the profiles in one or more assemblies into a configuration. AutoMapper provides the method AddProfiles method, which has several overloads that allow profiles to be loaded by passing the Assembly, specifying the assembly name, or specifying a type contai...

To easily convert all tables in one database, use the following: SET @DB_NAME = DATABASE(); SELECT CONCAT('ALTER TABLE `', table_name, '` ENGINE=InnoDB;') AS sql_statements FROM information_schema.tables WHERE table_schema = @DB_NAME AND `ENGINE` = 'MyISAM' AND `TABLE_TYPE` = '...

@Entity @Table(name="FOO") public class Foo { private UUID fooId; @OneToMany(mappedBy = "bar") private List<FooBar> bars; } @Entity @Table(name="BAR") public class Bar { private UUID barId; @OneToMany(mappedBy = "f...

@Entity @Table(name="FOO") public class Foo { private UUID fooId; @OneToMany @JoinTable(name="FOO_BAR", joinColumns = @JoinColumn(name="fooId"), inverseJoinColumns = @JoinColumn(name="barId")) private List<Bar&g...

@Entity @Table(name="FOO") public class Foo { private UUID fooId; @OneToMany @JoinTable(name="FOO_BAR", joinColumns = @JoinColumn(name="fooId"), inverseJoinColumns = @JoinColumn(name="barId", unique=true)) private ...

TestSchedulers allows you to control time and execution of Observables instead of having to do busy waits, joining threads or anything to manipulate system time. This is VERY important if you want to write unit tests that are predictable, consistent and fast. Because you are manipulating time, the...

Add the following directive before using any other mod_rewrite directive (RewriteRule, RewriteCond, RewriteBase or RewriteMap). RewriteEngine on By default the engine is turned off. mod_rewrite directives found while the engine is turned off are ignored. Enable it from within the virtual host co...

Important: Using the dynamic configuration files (.htaccess) is a big performance hit. When you have access to the static configuration file (httpd.conf or something similar) you should use that instead. In the static configuration file, allow dynamic configuration files to override "Filei...

An Observable can be thought of as just a stream of events. When you define an Observable, you have three listeners: onNext, onComplete and onError. onNext will be called every time the observable acquires a new value. onComplete will be called if the parent Observable notifies that it finished prod...

Creating a chart that displays a static dataset is relatively simple. For example, if we have this array of objects as the data: var data = [ {title: "A", value: 53}, {title: "B", value: 12}, {title: "C", value: 91}, {title: "D", value: 24...

To get a list of available serial ports use python -m serial.tools.list_ports at a command prompt or from serial.tools import list_ports list_ports.comports() # Outputs list of available serial ports from the Python shell.