Pick a random element from an array in Ruby

There are many different methods that allow mapping an Array to a Hash in Ruby.

Array#to_h with a block (Ruby 2.6+)

You can call an array with a block that is called with each element. The block must return a [key, value] tuple.

This i...

jQuery's removeClass removes the given class string from an element collection. If you want to remove multiple/unknown classes matching a given pattern, you can do that.

For example, consider a DOM node for the following HTML. We'll reference i...

So you have a restangular collection and you want to remove an element from it, after you've successfully deleted it from the server.

The README [suggests](https://github.com/mgonto/restangular#how-do-i-ha...

When a Ruby block or proc takes multiple parameters, and you call it with an Array, Ruby will unexpectedly splat the array elements:

block = proc { |a, b| "a=#{a}, b=#{b}" }
block.call(1, 2)   # "a=1, b=2"
block.call([1, 2]) # "a=1,...

If you want to grow a Ruby Array, you might find out about #fill but it is not really what you are looking for. [1]
For arrays of unknown size that you want to grow or shrink to a fixed size, you need to define something yourself. Like the follo...

In order to cover some edge cases you rarely care about, Range#include? will become very slow in Ruby 1.9:

Range#include? behaviour has changed in ruby 1.9 for non-numeric ranges. Rather...

Microsoft Exchange service administrators can enable Exchange Web Services (EWS) which is a rather accessible XML API for interacting with Exchange. This allows you to rea...

If you want to iterate over a Range, but only look at every n-th element, use the step method:

(0..10).step(5).each do |i|
  puts i
end

# Prints three lines...

When you need information about a gem (like version(s) or install path(s)), you can use the gem binary from the command line, or the Gem API inside a ruby process at runtime.

gem binary (in a terminal)

You can get some information abou...

When using form_for you can give the form's target URL either as a string or an array:

form_for(admin_user_path(@user)) do ... end
# same as:
form_for([:admin, @user]) do ... end

Same for link_to:

link_to("Label", edit_admin_u...