usernameGenerator | simple script that creates potential usernames

username.join(nameExtra) means "take each of the characters in nameExtra, and put the full value of username between each of them". This is why it's appearing several times. To fix this problem, do username + nameExtra instead of username.join(nameExtra).

Also, you're not building a string correctly, so it's using . at 0x0000020B09A5DE48> as the string, instead of the text you wanted it to use. To fix this problem, do ''.join(str(random.randint(0, 9)) for i in range(2)) instead of ''.join(str(random.randint(0, 9) for i in range(2))). Note the subtle difference in the closing parentheses.

Using callbacks is probably the most common way of doing async programming in JavaScript (and Node.js). However as of ES2017, one can use Promises in conjunction with async/await to write some non-blocking-async code which looks like synchronous code.

We can rewrite getAdminId function so it returns a promise instead of returning values in the callback (which doesn't work anyways because in CPS programming return values in callbacks don't matter):

Sorry, my previous answer was irrelevant to your issue. I'm writing a new better one now.

So, you generate some sequence of eight NON-UNIQUE characters. Say, it is "koabwbaq". Then you use

I am looking through the double for each loop and I believe I have narrowed down your issue. In the second for each loop, you print out the name of the person followed by the comma. But you do this for every element, including the last one. Include a conditional in there that once it reaches the length of the row, only print out the name not the comma.

You should change your code like below

inside main method

Everything looks right in your code.

I think you should just call the method when you are trying to print it out:

As @phatfingers commented, a TreeSet will respect the natural order of the entries in the set.

Since Codes2 already implements Comparable, you could simply replace your original HashSet with a TreeSet and call it a day.

Note this from the TreeSet documentation, however:

Note that the ordering maintained by a set (whether or not an explicit comparator is provided) must be consistent with equals if it is to correctly implement the Set interface. (See Comparable or Comparator for a precise definition of consistent with equals.) This is so because the Set interface is defined in terms of the equals operation, but a TreeSet instance performs all element comparisons using its compareTo (or compare) method, so two elements that are deemed equal by this method are, from the standpoint of the set, equal. The behavior of a set is well-defined even if its ordering is inconsistent with equals; it just fails to obey the general contract of the Set interface. (emphasis added)

What this means is that, while simply using a TreeSet probably work by itself, you may still want to consider overriding equals() and hashCode() in your Codes2 class so that the ordering behavior is consistent with equals.

You need to override the equals and hashCode methods on your Person object in order for Set to know which objects are considered the same.

It seems you want any two people with the same userNameGenerator field to be considered equal. In that case, the following will suit your needs: