Tutorial by Examples: ch

class Plane { enum Emergency: ErrorType { case NoFuel case EngineFailure(reason: String) case DamagedWing } var fuelInKilograms: Int //... init and other methods not shown func fly() throws { // ... if fuelInKilograms ...

If while working you realize you're on wrong branch and you haven't created any commits yet, you can easily move your work to correct branch using stashing: git stash git checkout correct-branch git stash pop Remember git stash pop will apply the last stash and delete it from the stash list. T...

9 Patches are stretchable images in which the areas which can be stretched are defined by black markers on a transparent border. There is a great tutorial here. Despite being so old, it's still so valuable and it helped many of us to deeply understand the 9 patch gear. Unfortunately, recently tha...

This example demonstrates creating a basic application in ExtJS using Sencha Cmd to bootstrap the process - this method will automatically generate some code and a skeleton structure for the project. Open a console window and change the working directory to an appropriate space in which to work. ...

The slider provides an event called change that will trigger after the mouse completes a slider handle drag or if the value(s) have been changed programmatically. This function holds a reference to the slide event and a reference to the slider ui object. The ui object holds a jQuery object for the ...

The HEALTHCHECK instruction has two forms: HEALTHCHECK [OPTIONS] CMD command (check container health by running a command inside the container) HEALTHCHECK NONE (disable any healthcheck inherited from the base image) The HEALTHCHECK instruction tells Docker how to test a container to check that...

SQL Server 2012 FETCH is generally more useful for pagination, but can be used as an alternative to TOP: SELECT * FROM table_name ORDER BY 1 OFFSET 0 ROWS FETCH NEXT 50 ROWS ONLY

This script, from here and here, will return all Tables and Columns where a specified value exists. This is powerful in finding out where a certain value is in a database. It can be taxing, so it is suggested that it be executed in a backup / test enviroment first. DECLARE @SearchStr nvarchar(100) ...

According to this [TechNet Microsoft page][1], Partitioning data enables you to manage and access subsets of your data quickly and efficiently while maintaining the integrity of the entire data collection. When you call the following query the data is not physically moved; only the metadata ab...

docker network disconnect app-backend myAwesomeApp-1 This command detaches the myAwesomeApp-1 container from the app-backend network. The container will no longer be able to communicate with other containers on the network it has been disconnected from, nor use the embedded DNS resolver to look u...

Many interesting operations in common JavaScript programming environments are asynchronous. For example, in the browser we see things like window.setTimeout(() => { console.log("this happens later"); }, 100); and in Node.js we see things like fs.readFile("file.txt", (...

An Akka MessageDispatcher is what makes Akka Actors "tick", it is the engine of the machine so to speak. All MessageDispatcher implementations are also an ExecutionContext, which means that they can be used to execute arbitrary code, for instance Futures. Every ActorSystem will have a def...

So in case you want to give your Actor a different dispatcher than the default, you need to do two things, of which the first is to configure the dispatcher in your application.conf: my-dispatcher { # Dispatcher is the name of the event-based dispatcher type = Dispatcher # What kind of Exe...

Using docker-machine is the best method to install Docker on a machine. It will automatically apply the best security settings available, including generating a unique pair of SSL certificates for mutual authentication and SSH keys. To create a local machine using Virtualbox: docker-machine create...

Listing docker-machines will return the state, address and version of Docker of each docker machines. docker-machine ls Will print something like: NAME ACTIVE DRIVER STATE URL SWARM DOCKER ERRORS docker-machine-1 - ovh Running ...

Upgrading a docker machine implies a downtime and may require planing. To upgrade a docker machine, run: docker-machine upgrade docker-machine-name This command does not have options

While attached to a running container with a pty assigned (docker run -it ...), you can press ControlP - ControlQ to detach.

With benchmark tests you can test and measure the speed of the code, however benchmark tests are still unstable. To enable benchmarks in your cargo project you need nightly rust, put your integration benchmark tests to the benches/ folder in the root of your Cargo project, and run cargo bench. Exam...

Here we demonstrate how to process lists recursively using OCaml's pattern matching syntax. let rec map f lst = match lst with | [] -> [] | hd::tl -> (f hd)::(map f tl) In this case, the pattern [] matches the empty list, while hd::tl matches any list that has at least one element...

You can use the microbenchmark package to conduct "sub-millisecond accurate timing of expression evaluation". In this example we are comparing the speeds of six equivalent data.table expressions for updating elements in a group, based on a certain condition. More specifically: A data....