Tutorial by Examples: l

Govendor is a tool that is used to import 3rd party packages into your code repository in a way that is compatible with golang's vendoring. Say for example that you are using a 3rd party package bosun.org/slog: package main import "bosun.org/slog" func main() { slog.Infof(&quo...

A flags-style enum value needs to be tested with bitwise logic because it may not match any single value. [Flags] enum FlagsEnum { Option1 = 1, Option2 = 2, Option3 = 4, Option2And3 = Option2 | Option3; Default = Option1 | Option3, } The Default value is actually a ...

NSAttributedString (and its mutable sibling NSMutableAttributedString) allows you to create strings that are complex in their appearance to the user. A common application is to use this to display a string and adding custom kerning / letter-spacing. This would be achieved as follows (where label ...

Method overloading, also known as function overloading, is the ability of a class to have multiple methods with the same name, granted that they differ in either number or type of arguments. Compiler checks method signature for method overloading. Method signature consists of three things - Met...

CGRect boundingRect = CGRectMake(-150, -150, 300, 300); CAKeyframeAnimation *orbit = [CAKeyframeAnimation animation]; orbit.keyPath = @"position"; orbit.path = CFAutorelease(CGPathCreateWithEllipseInRect(boundingRect, NULL)); orbit.duration = 4; orbit.additive = YES; orbit.repeatC...

Sometimes Data::Dumper is not enough. Got a Moose object you want to inspect? Huge numbers of the same structure? Want stuff sorted? Colored? Data::Printer is your friend. use Data::Printer; p $data_structure; Data::Printer writes to STDERR, like warn. That makes it easier to find the outpu...

Step 1 If you already have Django installed, you can skip this step. pip install Django Step 2 Create a new project django-admin startproject hello That will create a folder named hello which will contain the following files: hello/ ├── hello/ │ ├── __init__.py │ ├── settings.py │...

var availableName; do { availableName = getRandomName(); } while (isNameUsed(name)); A do while loop is guaranteed to run at least once as it's condition is only checked at the end of an iteration. A traditional while loop may run zero or more times as its condition is checked at the begin...

Although not strictly required, it is highly recommended to start your project in a "virtual environment." A virtual environment is a container (a directory) that holds a specific version of Python and a set of modules (dependencies), and which does not interfere with the operating system'...

Detailed instructions on getting emacs set up or installed. Official instructions are available on the GNU Emacs website. Debian systems On systems with the Debian package manager (such as Debian, Ubuntu, and Mint) Emacs can be installed via the simple command: sudo apt-get install emacs For ...

Tkinter comes pre-installed with the Python installer binaries for Mac OS X and the Windows platform. So if you install Python from the official binaries for Mac OS X or Windows platform, you are good to go with Tkinter. For Debian versions of Linux you have to install it manually by using the foll...

XML is made of basic building blocks, which are: element text attributes comments processing instructions An element has angle brackets: <element/> <element>some content</element> An attribute appears in an opening element tag: <element attribute-name="...

An XML document is a text file that conforms to the XML specification's well-formedness rules. Such a conforming document is said to be well-formed (not to be confused with valid). XML is very strict with well-formedness in comparison to other languages such as HTML. A text file that is not well-for...

The internal keyword makes a class (including nested classes), property, method or field available to every consumer in the same assembly: internal class Foo { internal string SomeProperty {get; set;} } internal class Bar { var myInstance = new Foo(); internal string SomeField ...

docker run --restart=always -d <container> By default, Docker will not restart containers when the Docker daemon restarts, for example after a host system reboot. Docker provides a restart policy for your containers by supplying the --restart command line option. Supplying --restart=always ...

Const ForReading = 1 Const ForWriting = 2 Const ForAppending = 8 Sub FsoExample() Dim fso As Object ' declare variable Set fso = CreateObject("Scripting.FileSystemObject") ' Set it to be a File System Object ' now use it to check if a file exists Dim myFilePath A...

Const ForReading = 1 Const ForWriting = 2 Const ForAppending = 8 Sub ReadTextFileExample() Dim fso As Object Set fso = CreateObject("Scripting.FileSystemObject") Dim sourceFile As Object Dim myFilePath As String Dim myFileText As String myFilePath = &...

Sub CreateTextFileExample() Dim fso As Object Set fso = CreateObject("Scripting.FileSystemObject") Dim targetFile As Object Dim myFilePath As String Dim myFileText As String myFilePath = "C:\mypath\to\myfile.txt" Set targetFile = fso.CreateT...

Const ForReading = 1 Const ForWriting = 2 Const ForAppending = 8 Sub WriteTextFileExample() Dim oFso Set oFso = CreateObject("Scripting.FileSystemObject") Dim oFile as Object Dim myFilePath as String Dim myFileText as String myFilePath = "C:\my...

traverse_ executes an Applicative action for every element in a Foldable structure. It ignores the action's result, keeping only the side-effects. (For a version which doesn't discard results, use Traversable.) -- using the Writer applicative functor (and the Sum monoid) ghci> runWriter $ trave...