It is probably not a shock to most of you, but I really enjoy answering code golf questions in Vim. There are many vim plugins that could greatly shorten some answers. For example, surround, subvert, easymotion, and many others could potentially save many bytes on the right challenge.
I've been wondering whether it would/should be allowed for a while, and it seems like the current consensus is contradictory. For example, as Mego wrote in this answer (+14/-0 right now):
Using a third-party library/module/extension/whatever has always been allowed by default. It should be noted in the answer that it is not the "vanilla" language
(something like Language + Library/Libraries is the most common way).
What you do get for free is the assumption that a certain third-party library (or set of third-party libraries) is present on the machine, and can be used via the normal mechanisms of the language.
This seems to imply that adding plugins is fine, and should cost no penalty. However as I myself wrote in this answer (+12/-0 right now):
On PPCG, languages are defined by their implementation. This includes any configuration files. Therefore, if you edit your local configuration files, you are essentially creating a new unpublished implementation of an existing language.
Presumably any language that might benefit from tweaking defaults would also have a way to edit that behavior inside of your solution, and however many bytes of boilerplate that takes is a reasonable byte handicap.
Here is where the problem arises. In Vim, the only way to install a plugin is to edit your
.vimrc to source the relevant files. Although you could manually source them, this feels very weird because a) it's not the traditional way of installing a plugin, b) vim submissions rarely need to use much vimscript, which sourcing plugins is entirely vimscript, and c) sourcing plugins is so verbose, solutions manually doing this will never be competitive.
So this brings up several questions.
Can plugins be installed for vim answers?
If so, can they be installed the normal way, by editing the
.vimrcor must they be manually sourced? If they can be installed the normal way, is there any byte penalty for using them?