Tutorial by Examples: b

Flexbox is a layout mode providing for the arrangement of elements on a page such that the elements behave predictably when the page layout must accommodate different screen sizes and different display devices. By default flexbox arranges children in a column. But you can change it to row using flex...
let list1 = [ 1; 2 ] let list2 = [ 1 .. 100 ] // Accessing an element printfn "%A" list1.[0] // Pattern matching let rec patternMatch aList = match aList with | [] -> printfn "This is an empty list" | head::tail -> printfn "This list consists o...
Create a .gitattributes file in the project root containing: * -text This is equivalent to setting core.autocrlf = false.
When contributors add to a project from different machines or operating systems, it may happen that they use different email addresses or names for this, which will fragment contributor lists and statistics. Running git shortlog -sn to get a list of contributors and the number of commits by them co...
Regular instances require: All instance types must be of the form (T a1 ... an) where a1 ... an are *distinct type variables*, and each type variable appears at most once in the instance head. That means that, for example, while you can create an instance for [a] you can't create an instance f...
Standard Haskell allows you to write integer literals in decimal (without any prefix), hexadecimal (preceded by 0x or 0X), and octal (preceded by 0o or 0O). The BinaryLiterals extension adds the option of binary (preceded by 0b or 0B). 0b1111 == 15 -- evaluates to: True
Database transactions ensure that a set of data changes will only be made permanent if every statement is successful. Any query or code failure during a transaction can be caught and you then have the option to roll back the attempted changes. PDO provides simple methods for beginning, committing,...
Lambda functions are anonymous functions which are usually created during a function call to act as a function parameter. They are declared by surrounding expressions with {braces} - if arguments are needed, these are put before an arrow ->. { name: String -> "Your name is $name&q...
Functions are declared using the fun keyword, followed by a function name and any parameters. You can also specify the return type of a function, which defaults to Unit. The body of the function is enclosed in braces {}. If the return type is other than Unit, the body must issue a return statement ...
One of the very basic animations that you could come across is the NumberAnimation. This animation works by changing the numeric value of a property of an item from an initial state to a final state. Consider the following complete example: import QtQuick 2.7 import QtQuick.Controls 2.0 ...
Django's default authentication works on username and password fields. Email authentication backend will authenticate users based on email and password. from django.contrib.auth import get_user_model class EmailBackend(object): """ Custom Email Backend to perform authent...
$string = "0| PHP 1| CSS 2| HTML 3| AJAX 4| JSON"; //[0-9]: Any single character in the range 0 to 9 // + : One or more of 0 to 9 $array = preg_split("/[0-9]+\|/", $string, -1, PREG_SPLIT_NO_EMPTY); //Or // [] : Character class // \d : Any digit // + : One or more ...
Routing defines a map between HTTP methods and URIs on one side, and actions on the other. Routes are normally written in the app/Http/routes.php file. In its simplest form, a route is defined by calling the corresponding HTTP method on the Route facade, passing as parameters a string that match...
ViewData is the mechanism for a controller to provide data to the view it presents, without using a ViewModel. Specifically, ViewData is a dictionary which is available both in MVC action methods and views. You may use ViewData to transfer some data from your action method to the view returned by th...
Create an application heroku create your-app-name Deploy to Heroku git push heroku master Open your application in a browser heroku open your-app-name List Heroku commands heroku commands General help heroku help Help for a specific command heroku help <command>
Using the apt package manager sudo apt-get update sudo apt-get install nodejs sudo apt-get install npm sudo ln -s /usr/bin/nodejs /usr/bin/node # the node & npm versions in apt are outdated. This is how you can update them: sudo npm install -g npm sudo npm install -g n sudo n stabl...
If an object is defined with static, thread, or automatic storage duration, and it has a character type, either: char, unsigned char, or signed char, it may not be accessed by a non-character type. In the below example a char array is reinterpreted as the type int, and the behavior is undefined on e...
use std::fs::File; use std::io::{BufRead, BufReader}; fn main() { let filename = "src/main.rs"; // Open the file in read-only mode (ignoring errors). let file = File::open(filename).unwrap(); let reader = BufReader::new(file); // Read the file line by line us...
You can validate request data using the validate method (available in the base Controller, provided by the ValidatesRequests trait). If the rules pass, your code will keep executing normally; however, if validation fails, an error response containing the validation errors will automatically be se...
In the Web App blade of the Azure Portal, click All settings > WebJobs to show the WebJobs blade: Click Add. The Add WebJob dialog appears. Under Name, provide a name for the WebJob. The name must start with a letter or a number and cannot contain any special characters other than...

Page 44 of 385