Tutorial by Examples: e

For lambdas with a single return statement, or multiple return statements whose expressions are of the same type, the compiler can deduce the return type: // Returns bool, because "value > 10" is a comparison which yields a Boolean result auto l = [](int value) { return value &gt...

If you specify the variable's name in the capture list, the lambda will capture it by value. This means that the generated closure type for the lambda stores a copy of the variable. This also requires that the variable's type be copy-constructible: int a = 0; [a]() { return a; // Ok, 'a' ...

On an ext filesystem, each file has a stored Access, Modification, and (Status) Change time associated with it - to view this information you can use stat myFile.txt; using flags within find, we can search for files that were modified within a certain time range. To find files that have been modifi...

To encode a string into a byte array, you can simply use the String#getBytes() method, with one of the standard character sets available on any Java runtime: byte[] bytes = "test".getBytes(StandardCharsets.UTF_8); and to decode: String testString = new String(bytes, StandardCharsets.U...

Tuples group multiple values into a single compound value. The values within a tuple can be of any type and do not have to be of the same type as each other. Tuples are created by grouping any amount of values: let tuple = ("one", 2, "three") // Values are read using index n...

Tuples can be decomposed into individual variables with the following syntax: let myTuple = (name: "Some Name", age: 26) let (first, second) = myTuple print(first) // "Some Name" print(second) // 26 This syntax can be used regardless of if the tuple has unnamed properti...

Functions can return tuples: func tupleReturner() -> (Int, String) { return (3, "Hello") } let myTuple = tupleReturner() print(myTuple.0) // 3 print(myTuple.1) // "Hello" If you assign parameter names, they can be used from the return value: func tupleReturner(...

If you want a function to be able to throw errors, you need to add the throws keyword after the parentheses that hold the arguments: func errorThrower()throws -> String {} When you want to throw an error, use the throw keyword: func errorThrower()throws -> String { if true { retur...

In this example we're going to look at testing webhook notifications in sandbox, using ngrok to provide a tunnel for our Node HTTP listener, running on localhost, to the internet. For this example, we're going to be using Node to set up notification webhooks for payment events (such as a payment bei...

Occasionally you will find the need to encode binary data as a base64-encoded string. For this we can use the DatatypeConverter class from the javax.xml.bind package: import javax.xml.bind.DatatypeConverter; import java.util.Arrays; // arbitrary binary data specified as a byte array byte[] bi...

Java SE 5 public enum Singleton { INSTANCE; public void execute (String arg) { // Perform operation here } } Enums have private constructors, are final and provide proper serialization machinery. They are also very concise and lazily initialized in a thread safe manne...

Writing bytes to an OutputStream one byte at a time OutputStream stream = object.getOutputStream(); byte b = 0x00; stream.write( b ); Writing a byte array byte[] bytes = new byte[] { 0x00, 0x00 }; stream.write( bytes ); Writing a section of a byte array int offset = 1; int length = ...

This sample will show you how to update an existing webhook forwarding URL (where the notifications should be POSTed to). To run this, you should have the ID provided back by PayPal when you first created your webhooks. First, add the PayPal SDK and configure the environment (sandbox below). var p...

Since the new line separator varies from platform to platform (e.g. \n on Unix-like systems or \r\n on Windows) it is often necessary to have a platform-independent way of accessing it. In Java it can be retrieved from a system property: System.getProperty("line.separator") Java SE 7 ...

To load a properties file bundled with your application: public class Defaults { public static Properties loadDefaults() { try (InputStream bundledResource = Defaults.class.getResourceAsStream("defaults.properties")) { Properties defaults = new ...

HTTPGetJSON performs an HTTP request to the specified URL and returns a jsonq.JsonQuery object for use in the alert template. Example: template example { {{ $ip := 8.8.8.8 }} {{ $whoisURL := printf "http://whois.arin.net/rest/ip/%s" $ip }} {{ $whoisJQ := $.HTTPGetJSON $who...

You can add an image to your message using the parameter media_url. # Download the twilio-python library from http://twilio.com/docs/libraries from twilio.rest import TwilioRestClient # Find these values at https://twilio.com/user/account account_sid = "ACXXXXXXXXXXXXXXXXX" auth_to...

To send your first SMS with Twilio and Python you'll just need the Twilio-Python helper library to get started. # Download the twilio-python library from http://twilio.com/docs/libraries from twilio.rest import TwilioRestClient # Find these values at https://twilio.com/user/account account_si...

To begin, install Node.js on your development computer. Windows: Navigate to the download page and download/run the installer. Mac: Navigate to the download page and download/run the installer. Alternatively, you can install Node via Homebrew using brew install node. Homebrew is a command-line pac...

There are different data types for different purposes. PHP does not have explicit type definitions, but the type of a variable is determined by the type of the value that is assigned, or by the type that it is casted to. This is a brief overview about the types, for a detailed documentation and exam...