Tutorial by Examples: ai

It is very common to get a StackOverflowError error while calling recursive function. Scala standard library offers TailCall to avoid stack overflow by using heap objects and continuations to store the local state of the recursion. Two examples from the scaladoc of TailCalls import scala.util.cont...

Lets create a simple transformation to convert a CSV into an XML file. Our Transformation has to do the following: Read the CSV file Build the greetings message Save the greetings in the XML file Create a Transformation: Here's how to start the Transformation: To the left of the works...

While the if ()... else statement allows to define only one (default) behaviour which occurs when the condition within the if () is not met, chaining two or more if () ... else statements allow to define a couple more behaviours before going to the last else branch acting as a "default", i...

Multiple comparison operators used together are chained, as if connected via the && operator. This can be useful for readable and mathematically concise comparison chains, such as # same as 0 < i && i <= length(A) isinbounds(A, i) = 0 < i ≤ length(A) # same as Set...

For live demo click.. App index ts import {bootstrap} from '@angular/platform-browser-dynamic'; import {MyForm} from './my-form.component.ts'; bootstrap(MyForm); Custom validator import {Control} from @'angular/common'; export class CustomValidators { static emailFormat(control: Cont...

Add the following method to check whether an email address is valid or not: private boolean isValidEmailId(String email){ return Pattern.compile("^(([\\w-]+\\.)+[\\w-]+|([a-zA-Z]{1}|[\\w-]{2,}))@" + "((([0-1]?[0-9]{1,2}|25[0-5]|2[0-4][0-9])\\.([0-1]?" ...

setuptools_scm is an officially-blessed package that can use Git or Mercurial metadata to determine the version number of your package, and find Python packages and package data to include in it. from setuptools import setup, find_packages setup( setup_requires=['setuptools_scm'], use_...

RAISERROR function will generate error in the TRY CATCH block: DECLARE @msg nvarchar(50) = 'Here is a problem!' BEGIN TRY print 'First statement'; RAISERROR(@msg, 11, 1); print 'Second statement'; END TRY BEGIN CATCH print 'Error: ' + ERROR_MESSAGE(); END CATCH RAISERROR ...

RAISERROR with severity (second parameter) less or equal to 10 will not throw exception. BEGIN TRY print 'First statement'; RAISERROR( 'Here is a problem!', 10, 15); print 'Second statement'; END TRY BEGIN CATCH print 'Error: ' + ERROR_MESSAGE(); END CATCH After RAISER...

You can re-throw error that you catch in CATCH block using TRHOW statement: DECLARE @msg nvarchar(50) = 'Here is a problem! Area: ''%s'' Line:''%i''' BEGIN TRY print 'First statement'; RAISERROR(@msg, 11, 1, 'TRY BLOCK', 2); print 'Second statement'; END TRY BEGIN CATCH print...

var firstItem = fetch("/api1").then(x => x.json()); var secondItem = fetch("/api2").then(x => x.json()); Promise.all([firstItem, secondItem]).spread((first, second) => { // access both results here, both requests completed at this point });

To list available DSC resources on your authoring node: Get-DscResource This will list all resources for all installed modules (that are in your PSModulePath) on your authoring node. To list all available DSC resources that can be found in the online sources (PSGallery ++) on WMF 5 : Find-DS...

Apart from primitives, the Explicit Layout structs (Unions) in C#, can also contain other Structs. As long as a field is a Value type and not a Reference, it can be contained in a Union: using System; using System.Runtime.InteropServices; // The struct needs to be annotated as "Explici...

Functional testing also can include testing processes that leave your environment, such as external API calls and emails. As an example, imagine you're functionally testing the registration process for your website. The final step of this process involves sending an email with an activation link. U...

Let's have a look at various options to wait for completion of tasks submitted to Executor ExecutorService invokeAll() Executes the given tasks, returning a list of Futures holding their status and results when everything is completed. Example: import java.util.concurrent.*; import ja...

The simple and most obvious way to use recursion to get the Nth term of the Fibonnaci sequence is this int get_term_fib(int n) { if (n == 0) return 0; if (n == 1) return 1; return get_term_fib(n - 1) + get_term_fib(n - 2); } However, this algorithm does not scale for higher ...

If there is no need for frontend in your next project, you can run sails new with additional flag --no-frontend. sails new NameOfProject --no-frontend This will generate everything needed for backend and will omit view, assets and grunt files. More about command line and sails-new: http://sails...

The following configuration options should be called on a Rails::Railtie object config.after_initialize: Takes a block which will be run after rails has initialized the application. config.asset_host: This sets the host for the assets. This is useful when using a Content Delivery Network. This i...

To get a list of available serial ports use python -m serial.tools.list_ports at a command prompt or from serial.tools import list_ports list_ports.comports() # Outputs list of available serial ports from the Python shell.

When an application has not been packaged as an executable JAR, you need to provide the name of an entry-point class on the java command line. Running the HelloWorld class The "HelloWorld" example is described in Creating a new Java program . It consists of a single class called HelloWo...