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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 ...

my $filename = '/path/to/file'; open my $fh, '<', $filename or die "Failed to open file: $filename"; # You can then either read the file one line at a time... while(chomp(my $line = <$fh>)) { print $line . "\n"; } # ...or read whole file into an arra...

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...

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...

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...

StackExchange.Redis also supports sending bytes over the pub/sub channel, here we use protobuf-net to serialize our message to a byte array before sending it: // definition of a message (marked up with Protobuf attributes) [ProtoContract] public class ChatMessage { [ProtoMember(1)] pub...

Property observers respond to changes to a property's value. var myProperty = 5 { willSet { print("Will set to \(newValue). It was previously \(myProperty)") } didSet { print("Did set to \(myProperty). It was previously \(oldValue)") } } m...

Users can add formatting to contenteditable documents or elements using their browser's features, such as common keyboard shortcuts for formatting (Ctrl-B for bold, Ctrl-I for italic, etc.) or by dragging and dropping images, links, or markup from the clipboard. Additionally, developers can use Jav...

package { import flash.display.Sprite; import flash.display.StageAlign; import flash.display.StageScaleMode; import flash.events.Event; public class Main extends Sprite { //Document Class Main Constructor public function Main() { ...

NSString *urlString = @"https://www.stackoverflow.com"; NSURL *myUrl = [NSURL URLWithString: urlString]; NSURL *myUrl2 = [NSURL URLWithString: urlString]; if ([myUrl isEqual:myUrl2]) return YES;

Express JS is the goto framework for developing Web Applications, APIs and almost any kind of Backend using Node. To install express, all you have to do is run the npm command npm install express --save And you're done. To create and run a new express server create a file app.js and add this ...

You can run logcat as an adb command or directly in a shell prompt of your emulator or connected device. To view log output using adb, navigate to your SDK platform-tools/ directory and execute: $ adb logcat Alternatively, you can create a shell connection to a device and then execute: $ adb sh...

Detailed instructions on getting mapbox set up or installed.

A Hash includes the Enumerable module, which provides several iteration methods, such as: Enumerable#each, Enumerable#each_pair, Enumerable#each_key, and Enumerable#each_value. .each and .each_pair iterate over each key-value pair: h = { "first_name" => "John", "last_na...