How can I detect in a Bash script if the current directory DOESN'T exist, and fail cleanly with a message like "Your current directory doesn't exist!" ?

So how can I write a script that would work in the following example?

```
$ mkdir /tmp/wow
$ cd /tmp/wow
$ pwd
/tmp/wow
$ rm -fr /tmp/wow
$ my_script.sh
Your current directory doesn't exist!

```