Regular expressions in Javascript are represented by a RegExp object. There also is a regex literal as in many other...

Activate VI mode by running set -o vi Now use your Bash as if it were VI! Hit Esc to...

While you usually do not need a Content-Type on GET request (which have a blank body), an external API...

Sometimes you want to know exactly how many objects exist within your running Ruby process. Here is how: stats = {} ObjectSpace.each...

Starting with Ruby 1.9, most #each methods can be called without a block, and will return an enumerator. This is...

This is how you regain disk space from OpenStack instances if you are using kvm and qcow. If your instance...

With ngAnimate, you can easily animate certain events (see directive support). We'll make use of ngClass animations to style...

Bash stores the exitcodestatus of piped commands in the environment variable PIPESTATUS So you can just echo ${PIPESTATUS[@]} to get...

We organize our daily work with issues in our Linear workspace. Issue format A good issue needs to be precise...

You have the following HTML structure:

If you want to run Javascript code whenever someone clicks on a ...

..., you...

To update your Rubygems to the latest available version, type the following: gem update --system Note that you have a...

On Ruby 1.9+, standard ruby character classes like \w, \d will only match 7-Bit ASCII characters: "foo" =~ /\w+/ # matches...

Understand how asynchronous JavaScript works: Read Henning's presentation about asynchronous Javascript (there's also a German video presentation...

If you are writing any amount of Javascript, you are probably using closures to hide local state, e.g. to have...

Learn Enough Command Line to be Dangerous (it's in our library => Google Drive) CLI tricks every developer should...

Rails is our web framework. Goals Be able to write a simple Rails application. Understand how Rails talks to the...

Ruby is the programming language we use on the backend. Goals After finishing this lesson you should be able to...

When you register a delegated event using on (or the deprecated delegate / live), it is somewhat hard to manually trigger...

If you want to grow a Ruby Array, you might find out about #fill but it is not really what...

When ending a Selenium test Capybara resets the browser state by closing the tab, clearing cookies, localStorage, etc.

Often times you want to give a bunch of elements the same style, except for the last. For example borders...

Write a // and indent every subsequent line by two spaces. This is great for documenting BEM blocks! // An action button...

When a CSS3 animation makes the animated element flicker, it may well be due to pixel fragments being handled differently...

jQuery doesn't store information about event listeners and data values with the element itself. This information is instead stored...