Readable booleans

Here is a trick I've learned from James Edward Gray II.

Have a look at this code. How can we improve it?

<%= rating_stars(..., true) %>

Looking at this line we have no idea what this "true" is actually responsible for and we'll have to go to the definition of rating_stars to find out.

There we will find:

def rating_stars(..., clickable = false)
  # ...
end

Ok, the boolean variable is responsible for the rating being clickable/non-clickable.

Now, since everything except false and nil is true in Ruby, we can improve the original line by using a meaningful symbol instead of true:

<%= rating_stars(..., :clickable) %>

Now, the code says: "return me a rating that is clickable".

Much more clear than the original version.