Tutorial by Examples: me

Consider the following dictionaries: >>> fish = {'name': "Nemo", 'hands': "fins", 'special': "gills"} >>> dog = {'name': "Clifford", 'hands': "paws", 'color': "red"} Python 3.5+ >>> fishdog = {**fish, **dog}...

$(window).load() was deprecated in jQuery version 1.8 (and completely removed from jQuery 3.0) and as such should not be used anymore. The reasons for the deprecation are noted on the jQuery page about this event Caveats of the load event when used with images A common challenge developers attem...

If you want your script to wait until a certain resource was loaded, such as an image or a PDF you can use .load(), which is a shortcut for shortcut for .on( "load", handler). HTML <img src="image.jpeg" alt="image" id="image"> jQuery $( "#imag...

When you need to iterate over the list of jQuery elements. Consider this DOM structure: <div class="container"> <div class="red one">RED 1 Info</div> <div class="red two">RED 2 Info</div> <div class="red three"...

Returns the first element that matches the selector starting at the element and traversing up the DOM tree. HTML <div id="abc" class="row"> <div id="xyz" class="row"> </div> <p id="origin"> Hello &...

There are three types of comment: # This comment continues to the end of line -- This comment continues to the end of line /* This is an in-line comment */ /* This is a multiple-line comment */ Example: SELECT * FROM t1; -- this is comment CREATE TABLE stack( /*id_user int...

The process.env property returns an object containing the user environment. It returns an object like this one : { TERM: 'xterm-256color', SHELL: '/usr/local/bin/bash', USER: 'maciej', PATH: '~/.bin/:/usr/bin:/bin:/usr/sbin:/sbin:/usr/local/bin', PWD: '/Users/maciej', EDITOR: 'vi...

console.time() can be used to measure how long a task in your code takes to run. Calling console.time([label]) starts a new timer. When console.timeEnd([label]) is called, the elapsed time, in milliseconds, since the original .time() call is calculated and logged. Because of this behavior, you can ...

/// <summary> /// Gets displayName from DataAnnotations attribute /// </summary> /// <typeparam name="TModel"></typeparam> /// <typeparam name="TProperty"></typeparam> /// <param name="htmlHelper"></param> /// <pa...

The general format for namespaces is: <Company>.(<Product>|<Technology>)[.<Feature>][.<Subnamespace>]. Examples include: Fabrikam.Math Litware.Security Prefixing namespace names with a company name prevents namespaces from different companies from having the sa...

Active patterns are just simple functions. Like functions you can define additional parameters: let (|HasExtension|_|) expected (uri : string) = let result = uri.EndsWith (expected, StringComparison.CurrentCultureIgnoreCase) match result with | true -> Some true | _ -> N...

In MATLAB versions prior to R2014b, using the old HG1 graphics engine, it was not obvious how to create color coded 2D line plots. With the release of the new HG2 graphics engine arose a new undocumented feature introduced by Yair Altman: n = 100; x = linspace(-10,10,n); y = x.^2; p = plot(x,y,'r...

Let's say we have a class MyClass with no constructor argument: class MyClass In Scala we can instantiate it using below syntax: val obj = new MyClass() Or we can simply write: val obj = new MyClass But, if not paid attention, in some cases optional parenthesis may produce some unexpecte...

In JavaScript all arguments are passed by value. When a function assigns a new value to an argument variable, that change will not be visible to the caller: var obj = {a: 2}; function myfunc(arg){ arg = {a: 5}; // Note the assignment is to the parameter variable itself } myfunc(obj); conso...

Information The ABSTRACT and FINAL additions to the METHODS and CLASS statements allow you to define abstract and final methods or classes. An abstract method is defined in an abstract class and cannot be implemented in that class. Instead, it is implemented in a subclass of the class. Abstra...

A trick exists that can display an error message along with an assertion. Normally, you would write code like this void f(void *p) { assert(p != NULL); /* more code */ } If the assertion failed, an error message would resemble Assertion failed: p != NULL, file main.c, line 5 Ho...

Following code will release lock. lock(locker) { return 5; } For a detailed explanation, this SO answer is recommended.

An instance method is a method that's available on a particular instance of a class, after the instance has been instantiated: MyClass *instance = [MyClass new]; [instance someInstanceMethod]; Here's how you define one: @interface MyClass : NSObject - (void)someInstanceMethod; // "-&qu...

Collection initialization syntax can be used when instantiating any class which implements IEnumerable and has a method named Add which takes a single parameter. In previous versions, this Add method had to be an instance method on the class being initialized. In C#6, it can also be an extension me...

Life-cycle hooks are also exposed as DSL elements, where later invocations of the methods shown below will replace the contents of the respective hooks: val a = actor(new Act { whenStarting { testActor ! "started" } whenStopping { testActor ! "stopped" } }) The above i...