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Dynamic Arrays (Array Resizing and Dynamic Handling)

Due to not being Excel-VBA exclusive contents this Example has been moved to VBA documentation. Link: Dynamic Arrays (Array Resizing and Dynamic Handling)

excel-vba • Arrays

operator

Most of the built-in operators (including conversion operators) can be overloaded by using the operator keyword along with the public and static modifiers. The operators comes in three forms: unary operators, binary operators and conversion operators. Unary and binary operators requires at least o...

C# Language • Keywords

To find out who changed a file

// Shows the author and commit per line of specified file git blame test.c // Shows the author email and commit per line of specified git blame -e test.c file // Limits the selection of lines by specified range git blame -L 1,10 test.c

Git • Blaming

Set the URL namespace for a reusable app (Django 1.9+)

Configure your app's URLconf to automatically use a URL namespace by setting the app_name attribute: # In <myapp>/urls.py from django.conf.urls import url from .views import overview app_name = 'myapp' urlpatterns = [ url(r'^$', overview, name='overview'), ] This will set t...

Django • URL routing

Lambda Syntax

NOTE: This is only available in Scala 2.12+ (and in recent 2.11.x versions with the -Xexperimental -Xfuture compiler flags) A SAM type can be implemented using a lambda: 2.11.8 trait Runnable { def run(): Unit } val t: Runnable = () => println("foo") The type can optional...

Scala Language • Single Abstract Method Types (SAM Types)

Find Data in MongoDB Using Mongoose, Express.js Routes and $text Operator

Setup First, install the necessary packages with: npm install express cors mongoose Code Then, add dependencies to server.js, create the database schema and the name of the collection, create an Express.js server, and connect to MongoDB: var express = require('express'); var cors = require('...

Node.js • Mongoose Library

$this, self and static plus the singleton

Use $this to refer to the current object. Use self to refer to the current class. In other words, use $this->member for non-static members, use self::$member for static members. In the example below, sayHello() and sayGoodbye() are using self and $this difference can be observed here. cl...

PHP • Classes and Objects

Factorial calculation

The factorial of a number (denoted with !, as for instance 9!) is the multiplication of that number with the factorial of one lower. So, for instance, 9! = 9 x 8! = 9 x 8 x 7! = 9 x 8 x 7 x 6 x 5 x 4 x 3 x 2 x 1. So in code that becomes, using recursion: long Factorial(long x) { if (x < 1...

C# Language • Recursion

Basic Usage

The dot operator repeats the last action performed, for instance: file test.tx helo, World! helo, David! (cursor at [1][1]) Now perform a cwHello<Esc> (Change Word helo to Hello) Now the buffer looks like that: Hello, World! helo, David! (cursor at [1][5]) After typing j_ the cur...

vim • The dot operator

Create (and write to a) known, persistant temporary file

You can create temporary files which has a visible name on the file system which can be accessed via the name property. The file can, on unix systems, be configured to delete on closure (set by delete param, default is True) or can be reopened later. The following will create and open a named temp...

Python Language • tempfile NamedTemporaryFile

Initializing an array filled with a repeated non-default value

As we know we can declare an array with default values: int[] arr = new int[10]; This will create an array of 10 integers with each element of the array having value 0 (the default value of type int). To create an array initialized with a non-default value, we can use Enumerable.Repeat from the...

C# Language • Arrays

Event Delegation

Event delegation is a process which allow us to avoid adding event listeners to specific nodes; instead, the event listener is added to parent node. This mechanism utilizes the event propagation/bubbling to handle an event at a higher level element/node in the DOM instead of using the element on whi...

DOM • Events

Accessing int literals' attributes

You might have heard that everything in Python is an object, even literals. This means, for example, 7 is an object as well, which means it has attributes. For example, one of these attributes is the bit_length. It returns the amount of bits needed to represent the value it is called upon. x = 7 ...

Python Language • Common Pitfalls

Properties and Methods

A Scripting Dictionary object stores information in Key/Item pairs. The Keys must be unique and not an array but the associated Items can be repeated (their uniqueness is held by the companion Key) and can be of any type of variant or object. A dictionary can be thought of as a two field in-memory ...

VBA • Scripting.Dictionary object