Question

When I collect values from an array, I like using this ruby idiom:

users.collect &:email

But then when I want to join those values, I end up having to expand it like so:

users.collect { |user| user.email }.join(", ")

Is there a better way to do this?

Answer 1

I don’t see why you have to expand it. You can do this:

users.collect(&:email).join(', ')


# or you can use collect's alias, map, 
# which is a much better name for this operation :)
users.map(&:email).join(', ')

The & operator in this context is a Symbol#to_proc. It basically treats the symbol you supply as a method name that it should call on a receiver and return its result.