Tutorial by Examples: e

Method references allow predefined static or instance methods that adhere to a compatible functional interface to be passed as arguments instead of an anonymous lambda expression. Assume that we have a model: class Person { private final String name; private final String surname; ...

Start with an iterable which needs to be grouped lst = [("a", 5, 6), ("b", 2, 4), ("a", 2, 5), ("c", 2, 6)] Generate the grouped generator, grouping by the second element in each tuple: def testGroupBy(lst): groups = itertools.groupby(lst, key=lambda...

Hashes can be understood as lookup-tables. You can access its contents by specifiying a key for each of them. Keys must be strings. If they're not, they will be converted to strings. If you give the hash simply a known key, it will serve you its value. # Elements are in (key, value, key, value) se...

HTML <p>My shadow always follows me.</p> CSS p { -webkit-filter: drop-shadow(10px 10px 1px green); filter: drop-shadow(10px 10px 1px green); } Result

To use multiple filters, separate each value with a space. HTML <img src='donald-duck.png' alt='Donald Duck' title='Donald Duck' /> CSS img { -webkit-filter: brightness(200%) grayscale(100%) sepia(100%) invert(100%); filter: brightness(200%) grayscale(100%) sepia(100%) invert(1...

HTML <img src='donald-duck.png' alt='Donald Duck' title='Donald Duck' /> CSS img { -webkit-filter: hue-rotate(120deg); filter: hue-rotate(120deg); } Result

HTML <div></div> CSS div { width: 100px; height: 100px; background-color: white; -webkit-filter: invert(100%); filter: invert(100%); } Result Turns from white to black.

A Bootstrap carousel is a Bootstrap component that creates a slideshow which cycles through elements within the carousel. Here is a basic HTML usage example: <div id="carousel-example-generic" class="carousel slide" data-ride="carousel"> <!-- Indicators --...

Carousel components can be instantiated via jQuery with the function $('.carousel').carousel(options), where $('.carousel') is a top-level reference to the specific carousel and options is a Javascript object specifying the carousel's default attributes. The options object allows for multiple prope...

Schema store: { "title": "JSON schema for the ASP.NET global configuration files", "$schema": "http://json-schema.org/draft-04/schema#", "type": "object", "additionalProperties": true, "required": [ &qu...

using System; using Xamarin.Forms; namespace NavigationApp { public class App : Application { public App() { MainPage = new NavigationPage(new FirstPage()); } } public class FirstPage : ContentPage { Label FirstPage...

Generally you should avoid using the default database role (often postgres) in your application. You should instead create a user with lower levels of privileges. Here we make one called niceusername and give it a password very-strong-password CREATE ROLE niceusername with PASSWORD 'very-strong-pas...

If we want to iterate backwards through a list or vector we can use a reverse_iterator. A reverse iterator is made from a bidirectional, or random access iterator which it keeps as a member which can be accessed through base(). To iterate backwards use rbegin() and rend() as the iterators for the e...

The arc4random_uniform() function is the simplest way to get high-quality random integers. As per the manual: arc4random_uniform(upper_bound) will return a uniformly distributed random number less than upper_bound. arc4random_uniform() is recommended over constructions like ''arc4random() % uppe...

The following code demonstrates usage of arc4random_uniform() to generate a random integer between 3 and 12: uint32_t randomIntegerWithinRange = arc4random_uniform(10) + 3; // A random integer between 3 and 12 This works to create a range because arc4random_uniform(10) returns an integer between...

hash( (1, 2) ) # ok hash( ([], {"hello"}) # not ok, since lists and sets are not hashabe Thus a tuple can be put inside a set or as a key in a dict only if each of its elements can. { (1, 2) } # ok { ([], {"hello"}) ) # not ok

One of the most common use of Sed is text substitution that can be achieved with the s command. In a terminal, type echo "Hello sed" | sed 's/sed/World/' and press Enter: $ echo "Hello sed" | sed 's/sed/World/' Hello World "Hello World" should be output to the ter...

Create an instance of UIScrollView with a CGRect as frame. Swift let scrollview = UIScrollView.init(frame: CGRect(x: 0, y: 0, width: 320, height: 400)) Objective-C UIScrollView *scrollview = [[UIScrollView alloc] initWithFrame:CGRectMake(0, 0, 320, 400)];

The contentSize property must be set to the size of the scrollable content. This specifies the size of the scrollable area. Scrolling is visible when scrollable area i.e. contentSize is larger than the UIScrollView frame size. With Autolayout: When the scroll view's content is set up using autolay...

When referring to a worksheet, a range or individual cells, it is important to fully qualify the reference. For example: ThisWorkbook.Worksheets("Sheet1").Range(Cells(1, 2), Cells(2, 3)).Copy Is not fully qualified: The Cells references do not have a workbook and worksheet associated ...