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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...

We can reference a function without actually calling it by prefixing the function's name with ::. This can then be passed to a function which accepts some other function as a parameter. fun addTwo(x: Int) = x + 2 listOf(1, 2, 3, 4).map(::addTwo) # => [3, 4, 5, 6] Functions without a receiv...

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 ...

If a function contains just one expression, we can omit the brace brackets and use an equals instead, like a variable assignment. The result of the expression is returned automatically. fun sayMyName(name: String): String = "Your name is $name"

Functions can be declared inline using the inline prefix, and in this case they act like macros in C - rather than being called, they are replaced by the function's body code at compile time. This can lead to performance benefits in some circumstances, mainly where lambdas are used as function param...

If you want to use the latest code, you can install it from the repository. While you potentially get new features and fixes, only numbered releases are officially supported. pip install https://github.com/pallets/flask/tarball/master

If you want to develop and contribute to the Flask project, clone the repository and install the code in development mode. git clone ssh://github.com/pallets/flask cd flask python3 -m venv env source env/bin/activate pip install -e . There are some extra dependencies and tools to be aware ...

Ajax Get: Solution 1: $.get('url.html', function(data){ $('#update-box').html(data); }); Solution 2: $.ajax({ type: 'GET', url: 'url.php', }).done(function(data){ $('#update-box').html(data); }).fail(function(jqXHR, textStatus){ alert('Error occured: ' + te...

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...

iex(1)> h List.last def last(list) Returns the last element in list or nil if list is empty. Examples ┃ iex> List.last([]) ┃ nil ┃ ┃ iex> List.last([1]) ┃ 1 ┃ ┃ iex> List.last([1, 2, 3]) ┃ 3

$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 ...

Dim array = New Integer() {1, 2, 3, 4} or Dim array As Int32() = {1, 2, 3, 4}

// View to hold the CAGradientLayer. let view: UIView = UIView(frame: CGRect(x: 0, y: 0, width: 320, height: 320)) // Initialize gradient layer. let gradientLayer: CAGradientLayer = CAGradientLayer() // Set frame of gradient layer. gradientLayer.frame = view.bounds // Color at the top of...

// View to hold the CAGradientLayer. let view: UIView = UIView(frame: CGRect(x: 0, y: 0, width: 320, height: 320)) // Initialize gradient layer. let gradientLayer: CAGradientLayer = CAGradientLayer() // Set frame of gradient layer. gradientLayer.frame = view.bounds // Color at the top of...

There are a number of collection types in Python. While types such as int and str hold a single value, collection types hold multiple values. Lists The list type is probably the most commonly used collection type in Python. Despite its name, a list is more like an array in other languages, mostl...

For instance, a computation involving commands to read and write from the prompt: First we describe the "commands" of our computation as a Functor data type {-# LANGUAGE DeriveFunctor #-} data TeletypeF next = PrintLine String next | ReadLine (String -> next) derivin...

Constructor functions are functions designed to construct a new object. Within a constructor function, the keyword this refers to a newly created object which values can be assigned to. Constructor functions "return" this new object automatically. function Cat(name) { this.name = name;...

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...

There are two parts of a class: the interface and the implementation. The interface is the exposed functionality of the class. Its public methods and variables are part of the interface. The implementation is the internal workings of a class. Other classes shouldn't need to know about the implemen...