Question

I’m using c-support in Vim. One of it’s features is the automatic comment expansion.

When I’m pasting code into Vim from an external editor, the comments are expanded (which gives me double-comments and messes up the paste – see below for example). I’d like to be able to disable the plugin, paste, then re-enable it, without relaunching Vim. I’m not sure if this is possible.

The SO questions here, here and here all describe methods to disable plugins, but they all require me to close Vim, mess with my .vimrc or similar, and relaunch; if I have to close Vim, I might as well cat file1 >> myfile; vim myfile, then shift the lines internally, which will be just as quick.

Is it possible to disable a plugin while running vim without relaunching, preferably in a way which allows me to map a hot-key toggle-plugin (so re-sourcing ~/.vimrc is alright; that’s mappable to a hotkey [I imagine, haven’t tried it yet])?

---

Messed up comments:

/*
 *  *  Authors:
 *   *    A Name 
 *    *
 *     *  Copyright:
 *      *    A Name, 2012
 *       */

---

EDIT: It turns out you can :set paste, :set nopaste (which, to quote :help paste, will “avoid unexpected effects [while pasting]”. (See the comments).
However, I’m still curious whether you can disable/enable a plugin as per the original question, so I shall leave the question open.

Answer 1

There is no general way of doing this without modifying plugin source. Some plugins (like all of mine) can add this feature (I have “unload” feature in my framework, but use it mainly for updating without restarting vim, not for temporary disabling something). What you can definitely do is to add a function call to each sourced plugin file that will save current vim state and also something that will do this after plugin was loaded (due to existance of finish, throw, try | <code with some error> you can’t just add this function at the end of the plugin), likely on VimEnter, FileType and Syntax events. Then you need to have a function that will revert changes done to the plugin and an s:Execute function definition in each plugin, like this:

function s:Execute_I_do_not_expect_function_with_this_suffix_to_be_defined_by_the_plugin_so_I_add_it_to_avoid_name_collisions(s)
    execute a:s
endfunction

. This is needed to execute a line of code in the context of sourced script. By “state” that needs to be saved I mean

1. Mappings
2. Commands
3. Signs
4. Functions
5. Menus
6. Events (autocommands)
7. Syntax (likely to be empty before plugin run)
8. Options
9. Some vim, all global, buffer, tab and window variables
10. // Script-local variables. Though it is simple here: at the start of the script script-local scope is empty and all you need is to empty it when disabling.

For each item it is possible to revert changes done by plugin, but it is not that easy to code. And presence of <script> argument to mappings is not distinguishable with presence of nore, though they have different behavior.

If you want to write it, do not forget about the fact that if script is resourced, your code will be relaunched.

Also, note the SourcePre event. It will help with automatic addition of your lines to all plugins.

Do not forget that there are more places that can be modified and can’t be saved and restored easily or at all: filesystem, interpreters state, opened plugin buffers, etc.