Working with special characters in a Mongo collection

I have a collection I'm unable to drop, I'm assuming that the "-" in its name is a special character. In MongoDB, what is the best way to escape special characters?

> db.tweets.drop();
true

BUT

> db.tweets-old.drop();
ReferenceError: old is not defined (shell):1

I've tried to escape with quotes (both single and double) and a slash, but nothing works.

The following works:

db["tweets-old"].drop();

It's called the square bracket notation, which allows you to use special characters in property names.

So does:

db.getCollection("tweets-old").drop()

And that has been around for a while now.

In addition, the method call also mimics what is the general "get a collection" accessor method in all officially supported MongoDB drivers. So the suggestion here is that you get used to using it this way, since the "named collection" accessor is how it is generally done.