The -Wildcard parameter allows switch statements to perform wildcard matching against conditions.
Example:
switch -Wildcard ('Condition')
{
'Condition' {'Normal match'}
'Condit*' {'Zero or more wildcard chars.'}
'C[aoc]ndit[f-l]on' {'Range and set of chars...
The -file parameter allows the switch statement to receive input from a file. Each line of the file is evaluated by the switch statement.
Example file input.txt:
condition
test
Example switch statement:
switch -file input.txt
{
'condition' {'First Action'}
'test' {'Second Action...
The Arbitrary class is for types that can be randomly generated by QuickCheck.
The minimal implementation of Arbitrary is the arbitrary method, which runs in the Gen monad to produce a random value.
Here is an instance of Arbitrary for the following datatype of non-empty lists.
import Test.QuickC...
% Define serial port with a baud rate of 115200
rate = 115200;
if ispc
s = serial('COM1', 'BaudRate',rate);
elseif ismac
% Note that on OSX the serial device is uniquely enumerated. You will
% have to look at /dev/tty.* to discover the exact signature of your
% serial device
...
It's possible to attach an object to an existing object as if there was a new property. This is called association and allows one to extend existing objects. It can be used to provide storage when adding a property via a class extension or otherwise add additional information to an existing object.
...
HTML5 data-* attributes provide a convenient way to store data in HTML elements. The stored data can be read or modified using JavaScript
<div data-submitted="yes" class="user_profile">
… some content …
</div>
Data attribute structure is data-*, i.e. the n...
<link rel="alternate stylesheet" href="path/to/style.css" title="yourTitle">
Some browsers allow alternate style sheets to apply if they are offered. By default they will not be applied, but usually they can be changed through the browser settings:
Firefox l...
If a case class has exactly two values, its extractor can be used in infix notation.
case class Pair(a: String, b: String)
val p: Pair = Pair("hello", "world")
val x Pair y = p
//x: String = hello
//y: String = world
Any extractor that returns a 2-tuple can work this way....
Similar to the while loop, only the control statement is evaluated after the loop. Therefore, the loop will always execute at least once.
var i: Int = 0
repeat {
print(i)
i += 1
} while i < 3
// 0
// 1
// 2
From NSString:
NSString *urlString = @"https://www.stackoverflow.com";
NSURL *myUrl = [NSURL URLWithString: urlString];
You can also use the following methods:
- initWithString:
+ URLWithString:relativeToURL:
- initWithString:relativeToURL:
+ fileURLWithPath:isDirectory:
- initF...
The operator for an "exclusive or" (for short XOR) is: ^
This operator returns true when one, but only one, of the supplied bools are true.
true ^ false // Returns true
false ^ true // Returns true
false ^ false // Returns false
true ^ true // Returns false
It's possible to declare protocol name without methods:
@protocol Person;
use it your code (class definition, etc):
@interface World : NSObject
@property (strong, nonatomic) NSArray<id<some>> *employees;
@end
and later define protocol's method somewhere in your code:
@protocol...
It is possible to bind values to names using @:
struct Badger {
pub age: u8
}
fn main() {
// Let's create a Badger instances
let badger_john = Badger { age: 8 };
// Now try to find out what John's favourite activity is, based on his age
match badger_john.age {
...
// Create a boolean value
let a = true;
// The following expression will try and find a pattern for our value starting with
// the topmost pattern.
// This is an exhaustive match expression because it checks for every possible value
match a {
true => println!("a is true"),
...
It's possible to treat multiple, distinct values the same way, using |:
enum Colour {
Red,
Green,
Blue,
Cyan,
Magenta,
Yellow,
Black
}
enum ColourModel {
RGB,
CMYK
}
// let's take an example colour
let colour = Colour::Red;
let model = match ...
Patterns can be matched based on values independent to the value being matched using if guards:
// Let's imagine a simplistic web app with the following pages:
enum Page {
Login,
Logout,
About,
Admin
}
// We are authenticated
let is_authenticated = true;
// But we aren't admins...
// 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...
