Tutorial by Examples: s

Swift NSNotificationCenter.defaultCenter().postNotificationName("TestNotification", object: self) Objective-C [[NSNotificationCenter defaultCenter] postNotificationName:@"TestNotification" object:nil];

Swift let userInfo: [String: AnyObject] = ["someKey": myObject] NSNotificationCenter.defaultCenter().postNotificationName("TestNotification", object: self, userInfo: userInfo) Objective-C NSDictionary *userInfo = [NSDictionary dictionaryWithObject:myObject forKey:@"som...

Swift func testNotification(notification: NSNotification) { let userInfo = notification.userInfo let myObject: MyObject = userInfo["someKey"] } Objective-C - (void)testNotification:(NSNotification *)notification { NSDictionary *userInfo = notification.userInfo; My...

Use Ctrl + C, Ctrl + C to exit iex(1)> BREAK: (a)bort (c)ontinue (p)roc info (i)nfo (l)oaded (v)ersion (k)ill (D)b-tables (d)istribution Use Ctrl+ \ to immediately exit

iex(1)> i :ok Term :ok Data type Atom Reference modules Atom iex(2)> x = "mystring" "mystring" iex(3)> i x Term "mystring" Data type BitString Byte size 8 Description This is a string: a UTF-8 encoded binary. It's printed surround...

#You can use pattern matching to run different #functions based on which parameters you pass #This example uses pattern matching to start, #run, and end a recursive function defmodule Counter do def count_to do count_to(100, 0) #No argument, init with 100 end def ...

Creating a DB and a Table DROP DATABASE IF EXISTS books_db; CREATE DATABASE books_db WITH ENCODING='UTF8' TEMPLATE template0; DROP TABLE IF EXISTS books; CREATE TABLE books ( id SERIAL PRIMARY KEY, client TEXT NOT NULL, data JSONb NOT NULL ); Populating the DB INSERT INTO books...

A standard toast notification appears at the bottom of the screen aligned in horizontal centre. You can change this position with the setGravity(int, int, int). This accepts three parameters: a Gravity constant, an x-position offset, and a y-position offset. For example, if you decide that the toas...

p { margin:1px; /* 1px margin in all directions */ /*equals to:*/ margin:1px 1px; /*equals to:*/ margin:1px 1px 1px; /*equals to:*/ margin:1px 1px 1px 1px; } Another exapmle: p{ margin:10px 15px; /...

g$ The above matches one letter (the letter g) at the end of a string in most regex engines (not in Oniguruma, where the $ anchor matches the end of a line by default, and the m (MULTILINE) modifier is used to make a . match any characters including line break characters, as a DOTALL modifier in ...

You can use subqueries to define a temporary table and use it in the FROM clause of an "outer" query. SELECT * FROM (SELECT city, temp_hi - temp_lo AS temp_var FROM weather) AS w WHERE temp_var > 20; The above finds cities from the weather table whose daily temperature variation i...

The following example finds cities (from the cities example) whose population is below the average temperature (obtained via a sub-qquery): SELECT name, pop2000 FROM cities WHERE pop2000 < (SELECT avg(pop2000) FROM cities); Here: the subquery (SELECT avg(pop2000) FROM cities) is used to s...

Subqueries can also be used in the SELECT part of the outer query. The following query shows all weather table columns with the corresponding states from the cities table. SELECT w.*, (SELECT c.state FROM cities AS c WHERE c.name = w.city ) AS state FROM weather AS w;

Elixir doesn't have loops. Instead of them for lists there are great Enum and List modules, but there are also List Comprehensions. List Comprehensions can be useful to: create new lists iex(1)> for value <- [1, 2, 3], do: value + 1 [2, 3, 4] filtering lists, using guard expressi...

NSArray *reversedArray = [myArray.reverseObjectEnumerator allObjects];

a = [1, 2, 3, true] Note that these are stored in memory as linked lists. Id est this is a series of cons cells where the head (List.hd/1) is the value of first item of the list and the tail (List.tail/1) is the value of the rest of the list. List.hd(a) = 1 List.tl(a) = [2, 3, true]

b = {:ok, 1, 2} Tuples are the equivalent of arrays in other languages. They are stored contiguously in memory.

CHICKEN is a Scheme interpreter and compiler with its own extension module system called "eggs". It is capable of compiling Scheme to native code by first compiling Scheme to C. Installing Debian or Ubuntu or other derived distros: sudo apt-get install chicken-bin Fedora / RHEL / Ce...

Once connected you can publish messages by calling the ISubscriber.Publish method: // grab an instance of an ISubscriber var subscriber = connection.GetSubscriber(); // publish a message to the 'chat' channel subscriber.Publish("chat", "This is a message") Consumers can ...

You can broadcast more complex messages by serializing the payload before you publish it: // definition of a message public class ChatMessage { public Guid Id { get; set; } public string User { get; set; } public string Text { get; set; } } // grab an instance of an ISubscriber...