Tutorial by Examples: l

Listing available remote versions for installation nvm ls-remote Installing a remote version nvm install <version> For example nvm install 0.10.13

To list available local versions of node through NVM: nvm ls For example, if nvm ls returns: $ nvm ls v4.3.0 v5.5.0 You can switch to v5.5.0 with: nvm use v5.5.0

Three methods are provided that offer the ability to strip leading and trailing characters from a string: str.strip, str.rstrip and str.lstrip. All three methods have the same signature and all three return a new string object with unwanted characters removed. str.strip([chars]) str.strip acts o...

To connect using java.sql.DriverManager you need a JDBC url to connect to your database. JDBC urls are database specific, but they are all of the form jdbc:<subprotocol>:<subname> Where <subprotocol> identifies the driver or database (for example postgresql, mysql, firebirdsql,...

When you deploy your app to a (Node.js-specific) hosted environment, this environment usually offers a PORT-environment variable that you can use to run your server on. Changing the port number to process.env.PORT allows you to access the application. For example, http.createServer(function(reques...

You can use the node-inspector. Run this command to install it via npm: npm install -g node-inspector Then you can debug your application using node-debug app.js The Github repository can be found here: https://github.com/node-inspector/node-inspector Debugging natively You can also debu...

Tips & Tricks to avoid nasty situations EC2 Instances and EBS Set IAM Roles. Unlike tags, the IAM Role is set once and for all on EC2 instanciation (even after 4 years) ! Try to identify and categorize beforehand your instances so you can give an them appropriate IAM roles. IAM Roles are ...

The intrinsic pack function packs an array into a vector, selecting elements based on a given mask. The function has two forms PACK(array, mask) PACK(array, mask, vector) (that is, the vector argument is optional). In both cases array is an array, and mask of logical type and conformable with...

Consider the following component with one input myInput and an internal value called someInternalValue. Both of them are used in a component's template. import {Component, Input} from '@angular/core'; @Component({ template:` <div> <p>{{myInput}}</p> <p>{...

trait Hello { public function sayHello() { echo 'Hello '; } } trait World { public function sayWorld() { echo 'World'; } } class MyHelloWorld { use Hello, World; public function sayExclamationMark() { echo '!'; } } $o = new My...

trait HelloWorld { public function sayHello() { echo 'Hello World!'; } } // Change visibility of sayHello class MyClass1 { use HelloWorld { sayHello as protected; } } // Alias method with changed visibility // sayHello visibility not changed class MyClass2 { u...

Consider this broken snippet: def foo bar = [1, 2, 3, 4].map do |x| return 0 if x.even? x end puts 'baz' bar end foo # => 0 One might expect return to yield a value for map's array of block results. So the return value of foo would be [1, 0, 3, 0]. Instead, return retu...

The following compares two files with diff using process substitution instead of creating temporary files. diff <(curl http://www.example.com/page1) <(curl http://www.example.com/page2)

This feeds a while loop with the output of a grep command: while IFS=":" read -r user _ do # "$user" holds the username in /etc/passwd done < <(grep "hello" /etc/passwd)

Problem: Some data needs to be passed to a scene loaded from a fxml. Solution Specify a controller using the fx:controller attribute and get the controller instance created during the loading process from the FXMLLoader instance used to load the fxml. Add methods for passing the data to the contr...

Problem: Some data needs to be passed to a scene loaded from a fxml. Solution Set the controller using the FXMLLoader instance used later to load the fxml. Make sure the controller contains the relevant data before loading the fxml. Note: in this case the fxml file must not contain the fx:contro...

Problem: Some data needs to be passed to a scene loaded from a fxml. Solution Specify a controller factory that is responsible for creating the controllers. Pass the data to the controller instance created by the factory. FXML <?xml version="1.0" encoding="UTF-8"?> &...

LinqPad is a great tool that allows you to learn and test features of .Net languages (C#, F# and VB.Net.) Install LinqPad Create a new Query (Ctrl + N) Under language, select "C# statements" Type the following code and hit run (F5) string hw = "Hello World&quo...

Type variables are uncapitalized names in type-signatures. Unlike their capitalized counterparts, such as Int and String, they do not represent a single type, but rather, any type. They are used to write generic functions that can operate on any type or types, and are particularly useful for writing...

Sometimes we want to give a type a more descriptive name. Let's say our app has a data type representing users: { name : String, age : Int, email : String } And our functions on users have type signatures along the lines of: prettyPrintUser : { name : String, age : Int, email : String } -> S...