I've started using Vim to develop Perl scripts and am starting to find it very powerful.

One thing I like is to be able to open multiple files at once with:

vi main.pl maintenance.pl

and then hop between them with:

:n
:prev

and see which file are open with:

:args

And to add a file, I can say:

:n test.pl

which I expect would then be added to my list of files, but instead it wipes out my current file list and when I type :args I only have test.pl open.

So how can I add and remove files in my args list?