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If we have a struct like this struct Box { let name: String let thingsInside: Int } and an array of Box(es) let boxes = [ Box(name: "Box 0", thingsInside: 1), Box(name: "Box 1", thingsInside: 2), Box(name: "Box 2", thingsInside: 3), B...

Some attributes are directly accessible as properties of the element (e.g. alt, href, id, title and value). var a = document.querySelector("a"), url = a.href; Other attributes, including data-attributes can be accessed as follows: var a = document.querySelector("a"), ...

Download Heroku Toolbelt. Navigate to the root of the sources of your Django app. You'll need tk Type heroku create [app_name]. If you don't give an app name, Heroku will randomly generate one for you. Your app URL will be http://[app name].herokuapp.com Make a text file with the ...

Values can be given names using let: # let a = 1;; val a : int = 1 You can use similar syntax to define a function. Just provide additional parameters for the arguments. # let add arg1 arg2 = arg1 + arg2;; val add : int -> int -> int = <fun> We can call it like this: # add 1...

The function keyword automatically has pattern matching when you define the body of your function. Observe it below: # let foo = function 0 -> "zero" | 1 -> "one" | 2 -> "couple" | 3 -> "few" | _ -> "many";; val foo : int -&gt...

Classes, structures, and enumerations can define subscripts, which are shortcuts for accessing the member elements of a collection, list, or sequence. Example struct DaysOfWeek { var days = ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri"...

3.0 let string = "My fantastic string" var index = string.startIndex while index != string.endIndex { print(string[index]) index = index.successor() } Note: endIndex is after the end of the string (i.e. string[string.endIndex] is an error, but string[string.startIndex] i...

A defer statement in Go is simply a function call marked to be executed at a later time. Defer statement is an ordinary function call prefixed by the keyword defer. defer someFunction() A deferred function is executed once the function that contains the defer statement returns. Actual call to th...

[1, 2, [[3, 4], [5]], 6].flatten # => [1, 2, 3, 4, 5, 6] If you have a multi-dimensional array and you need to make it a simple (i.e. one-dimensional) array, you can use the #flatten method.

In case you need to read an array elements avoiding repetitions you case use the #uniq method: a = [1, 1, 2, 3, 4, 4, 5] a.uniq #=> [1, 2, 3, 4, 5] Instead, if you want to remove all duplicated elements from an array, you may use #uniq! method: a = [1, 1, 2, 3, 4, 4, 5] a.uniq! #=> [1...

Standard enumerations allow users to declare a useful name for a set of integers. The names are collectively referred to as enumerators. An enumeration and its associated enumerators are defined as follows: enum myEnum { enumName1, enumName2, }; An enumeration is a type, one which is...

A common use for enumerators is for switch statements and so they commonly appear in state machines. In fact a useful feature of switch statements with enumerations is that if no default statement is included for the switch, and not all values of the enum have been utilized, the compiler will issue ...

If targeting Flash Player 11+, the built-in removeChildren method is the best way to remove all children: removeChildren(); //a start and end index can be passed For legacy applications, the same can be accomplished with a loop: while (numChildren > 0) { removeChildAt(0); }

Enums in Swift are much more powerful than some of their counterparts in other languages, such as C. They share many features with classes and structs, such as defining initialisers, computed properties, instance methods, protocol conformances and extensions. protocol ChangesDirection { mutati...

Detailed instructions on getting date set up or installed.

package { import flash.events.TimerEvent; import flash.utils.Timer; public class CountdownTimer extends Timer { public var time:Number = 0; public function CountdownTimer(time:Number = Number.NEGATIVE_INFINITY, delay:Number = 1000) { super(delay, repeatCount); ...

Using functions that take in and execute closures can be extremely useful for sending a block of code to be executed elsewhere. We can start by allowing our function to take in an optional closure that will (in this case) return Void. func closedFunc(block: (()->Void)? = nil) { print("...

Note: Everything below applies to the str.format method, as well as the format function. In the text below, the two are interchangeable. For every value which is passed to the format function, Python looks for a __format__ method for that argument. Your own custom class can therefore have th...

// RawRepresentable has an associatedType RawValue. // For this struct, we will make the compiler infer the type // by implementing the rawValue variable with a type of String // // Compiler infers RawValue = String without needing typealias // struct NotificationName: RawRepresentable { ...

Select the .xcdatamodeld file. You will notice you have no entities. You will have to create one yourself. At the bottom of Xcode you will notice a button that says "Add Entity" click it and you will have a new entity for you to work with on the project. In this step there are ...