Handle delay when exiting into vim normal mode

Hello, @randy3k! I wanted to share my problem, its current workaround, and ask for any suggestions and possibilities of new radian settings.

By default, when using "vim" editing mode there is a rather long delay when exiting from insert into normal mode after hitting <Esc> key. It is tolerable if no radian.escape_key_map is defined and long otherwise.

I believe, it is present in order to enable escape_key_map functionality. However, I use those keymappings with <Alt> key so I don’t really need any delay when hitting <Esc>. I didn’t find any setting in radian which can help with this.

My current workaround is as follows. As radian uses Python’s ‘prompt_toolkit’, there is a way to modify that delay. Currently it is defined by ttimeoutlen and timeoutlen properties of Application class. Their default values are 0.5 and 1 seconds. After experimenting, it seems that delay of 0.5 is “used” when no escape_key_map is defined and 1.5 (0.5+1) otherwise. Inspired by this comment, I implemented the following workaround (which is added to ‘.radian_profile’):

options(
  radian.editing_mode = "vim",
  radian.on_load_hooks = list(function() {
    getOption("rchitect.py_tools")$attach()

    radian <- import("radian")
    app <- radian$get_app()$session$app

    # Modify timeout lengths (in seconds): time to wait after pressing <Esc>
    # for another key pressing. Very useful to reduce delay when going in
    # Normal mode under "vim" editing mode.
    app$ttimeoutlen <- 0
    # This shouldn't be too small, as it is used when dealing operator sequence
    # in normal mode
    app$timeoutlen  <- 0.25
  })
)

Currently this works for me. Is there any chance of getting “official” radian settings which can help with this issue? The ultimate solution would be two settings: enabling <Alt> key mappings instead of <Esc> and those [t]timeoutlens, but I don’t believe both of them are possible, are they?

[marskar]

@echasnovski, your solution is great. I was going to do something similar to change the cursor shape based on the current vim mode, but I decided to edit the Python code instead of writing an R hook in an option () call. I submitted a PR (#222) that changes both the cursor shape and [t]timeoutlens. You can find more info in the issue (#220) that preceded the PR.

[randy3k]

Your observation is correct. It is exactly how prompt toolkit handles the key bindings.