In regards to the Go integration, it's been decided it would be better to have a host like in the case of the python plugin, but the main rationale for that is not to create too many co-processes.
I know that the plugin API is still in flux, but I really wish it was documented anyway. Actually, I'm not even sure how anyone was even able to start coding something like this without a design doc existing first.
:python // executes python code, eg: :python print 1+1
:pyfile // executes a file, eg: :python pyfile test.py
:pydo // applies a python expression on a range, eg: 1,2pydo return int(line)+1
pyeval(...) // returns the value of ..., eg: :echo pyeval("1+1")
A go host, however, would possibly need to work differently. The idea for now is to have a process that checks for go files in a folder, and bundles them into a big executable that registers external functions in vim like a dynamic host would.
Nothing in the above means a plugin couldn't simply talk to neovim by itself, without using the host architecture. All a plugin needs is to talk to neovim thorough the msgpack-rpc api.
> I know that the plugin API is still in flux, but I really wish it was documented anyway. Actually, I'm not even sure how anyone was even able to start coding something like this without a design doc existing first.
Agreed. That's the goal of that discussion (I believe), to come up with a good design.
On one hand you can then implement the famous VIM UI on top of that (i.e. in the tty sense, a curses program that communicates with the server, sending stuff like "change word") and on the other hand it is really easy to make it scriptable in any language that supports sockets. Obviously the networking/parsing stuff would be hidden by a neovim <LANG$> module.
Obviously this would be a multi-process architecture but the number of processes would be really small and peanuts in a modern system. But anyway, thanks for your work!
/update: just read https://github.com/neovim/neovim/wiki/Plugin-UI-architecture so it IS the chosen architecture - never mind then!
Defining methods via msgpack-rpc and calling through vimscript is already possible(send_call will block until the connected plugin returns a response). Here's what Neovim still needs:
- A way to spawn plugins through vimscript. This was fixed [here](https://github.com/tarruda/neovim/commit/acf17dbefef379ecb8e...) and will replace the initpython/initclipboard options. This alone will be enough to implement the golang proposal.
- Modify vimscript to enable definition of lower cased functions and commands, and commands that accept heredocs. This will let us move the knowledge about other languages/interpreters from the C core to vimscript, though it has the disadvantage of introducing incompatibilities with vim in the future
> - A way to spawn plugins through vimscript. This was fixed [here](https://github.com/tarruda/neovim/commit/acf17dbefef379ecb8e...) and will replace the initpython/initclipboard options. This alone will be enough to implement the golang proposal.
This is neat.
Thanks for all the work, btw, tarruda. neovim is a great project, and you deserve a lot of credit for pushing ahead with it.
I've been avoiding to write documentation because the rpc infrastructure was still alpha, though that will probably change after #1130 is merged(I will write at least one comprehensive wiki entry)
> I'm not even sure how anyone was even able to start coding something like this without a design doc existing first.
This is just how I work: Instead of writing design docs, I start with an idea and the design is shaped while implementing the initial prototypes. Only after it's solid the docs will be created.