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local Class = {} -- objects and classes will be tables local __meta = {__index = Class} -- ^ if an instance doesn't have a field, try indexing the class function Class.new() -- return setmetatable({}, __meta) -- this is shorter and equivalent to: local new_instance = {} setmetatabl...

bsort :: Ord a => [a] -> [a] bsort s = case bsort' s of t | t == s -> t | otherwise -> bsort t where bsort' (x:x2:xs) | x > x2 = x2:(bsort' (x:xs)) | otherwise = x:(bsort' (x2:xs)) bsort' s = s

To process lists, we can simply pattern match on the constructors of the list type: listSum :: [Int] -> Int listSum [] = 0 listSum (x:xs) = x + listSum xs We can match more values by specifying a more elaborate pattern: sumTwoPer :: [Int] -> Int sumTwoPer [] = 0 sumTwoPer (x1...

pip doesn't current contain a flag to allow a user to update all outdated packages in one shot. However, this can be accomplished by piping commands together in a Linux environment: pip list --outdated --local | grep -v '^\-e' | cut -d = -f 1 | xargs -n1 pip install -U This command takes all pa...

pip doesn't current contain a flag to allow a user to update all outdated packages in one shot. However, this can be accomplished by piping commands together in a Windows environment: for /F "delims= " %i in ('pip list --outdated --local') do pip install -U %i This command takes all pa...

pip assists in creating requirements.txt files by providing the freeze option. pip freeze > requirements.txt This will save a list of all packages and their version installed on the system to a file named requirements.txt in the current folder.

pip assists in creating requirements.txt files by providing the freeze option. pip freeze --local > requirements.txt The --local parameter will only output a list of packages and versions that are installed locally to a virtualenv. Global packages will not be listed.

Class composition allows explicit relations between objects. In this example, people live in cities that belong to countries. Composition allows people to access the number of all people living in their country: class Country(object): def __init__(self): self.cities=[] ...

To make artisan migrate a fresh database before running tests, use DatabaseMigrations. Also if you want to avoid middleware like Auth, use WithoutMiddleware. <?php use Illuminate\Foundation\Testing\WithoutMiddleware; use Illuminate\Foundation\Testing\DatabaseMigrations; class ExampleTest ...

The steps of overload resolution are: Find candidate functions via name lookup. Unqualified calls will perform both regular unqualified lookup as well as argument-dependent lookup (if applicable). Filter the set of candidate functions to a set of viable functions. A viable function for whi...

really_neat.info name = Really Neat Module description = Provides a really neat page for your site core = 7.x really_neat.module <?php /** * @file * Hook implementation and shared functions for the Really Neat Module. */ /** * Implements hook_menu(). */ function really_nea...

Recursion can be defined as: A method that calls itself until a specific condition is met. An excellent and simple example of recursion is a method that will get the factorial of a given number: public int Factorial(int number) { return number == 0 ? 1 : n * Factorial(number - 1); } ...

In the timeline of any DisplayObject that is attached as a descendant of the display tree, you can utilise the root property. This property points to the main timeline in the case of no custom document class, or the document class if you do define one. Because root is typed DisplayObject, the compi...

Enums are iterable: class Color(Enum): red = 1 green = 2 blue = 3 [c for c in Color] # [<Color.red: 1>, <Color.green: 2>, <Color.blue: 3>]

The jsonlite package is a fast JSON parser and generator optimized for statistical data and the web. The two main functions used to read and write JSON are fromJSON() and toJSON() respecitively, and are designed to work with vectors, matrices and data.frames, and streams of JSON from the web. Creat...

Add this permission to the manifest file to use Bluetooth features in your application: <uses-permission android:name="android.permission.BLUETOOTH" /> If you need to initiate device discovery or manipulate Bluetooth settings, you also need to add this permission: <uses-permi...

private static final int REQUEST_ENABLE_BT = 1; // Unique request code BluetoothAdapter mBluetoothAdapter; // ... if (!mBluetoothAdapter.isEnabled()) { Intent enableBtIntent = new Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE); startActivityForResult(enableBtIntent, REQUEST_ENABLE_B...

private static final int REQUEST_DISCOVERABLE_BT = 2; // Unique request code private static final int DISCOVERABLE_DURATION = 120; // Discoverable duration time in seconds // 0 means always discoverable ...

Declare a BluetoothAdapter first. BluetoothAdapter mBluetoothAdapter; Now create a BroadcastReceiver for ACTION_FOUND private final BroadcastReceiver mReceiver = new BroadcastReceiver() { public void onReceive(Context context, Intent intent) { String action = intent.getAction(); //...

A list of recognised color keyword names can be found in the W3C Recommendation for SVG. <svg xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"> <circle r="30" cx="100" cy="100" fill="red" stroke=&qu...