Analogous to nodejs's `on('data', …)` interface, here on_key is the "add
listener" interface.
ref 3ccdbc570d#12536
BREAKING_CHANGE: vim.register_keystroke_callback() is now an error.
When a keymap is set from lua currently verbose message says
it's set from line 1. That's incorrect because we don't really know when
it was set. So until proper :verbose support isn't added for sourceing
lua it shouldn't say where it was set at.
Can be reproduced with a script like this:
-- in some lua file
vim.fn.timer_start(10, function() error("uh....") end)
-- will cause neovim to crash with the following error.
PANIC: unprotected error in call to Lua API
(nlua_CFunction_func_call failed.)
After this, it will instead print the error message
from the top of the stack, like so.
tmp/error_nvim.lua:10: uh...
Also added an example test. Previously this test
caused the embedded nvim to panic.
vim-patch:8.2.1054: not so easy to pass a lua function to Vim
vim-patch:8.2.1084: Lua: registering function has useless code
I think I have also opened up the possibility for people to use these
callbacks elsewhere, since I've added a new struct that we should be
able to use.
Also, this should allow us to determine what the state of a list is in
Lua or a dictionary in Lua, since we now can track the luaref as we go.
- We already find ourselves renaming nvim_execute_lua in tests and
scripts, which suggests "exec" is the verb we actually want.
- Add "exec" verb to `:help dev-api`.
- Add vim variable meta accessors: vim.env, vim.{g,v,w,bo,wo}
- Redo gen_char_blob to generate multiple blobs instead of just one
so that multiple Lua modules can be inlined.
- Reorder vim.lua inclusion so that it can use previously defined C
functions and utility functions like vim.shared and vim.inspect things.
- Inline shared.lua into nvim, but also keep it available in runtime.
compared to vim.api.|nvim_call_function|, this fixes some typing issues
due to the indirect conversion via the API. float values are preserved
as such (fixes#9389) as well as empty dicts/arrays.
Ref https://github.com/norcalli/nvim.lua for the call syntax
