Going back history with multiline commands

[romaia]

When my last command is a muiltiline comand, and I press up, the last command shows up, with the cursor at the very last of the command.

Now If I press up again, I go to the second last line, pressing up again, the third last line, and so on...

Can I configure some binding that instead of going up one line at a time (in the editor), I actually go back one command at a time?

IE: pressing C up shows the last command, pressing it again, shows the command before that (instead of going up one line)?

In other words: quickly go through history, even if there are multiline commands in the history.

[akinomyoga]

In the default binding, PageUp and PageDown are bound by the history prefix search. If the history prefix search is started with an empty command line, it actually moves one history entry for every keypress.

If you would like to configure C-up and C-down for the actual history movement, you can use the following settings:

function my/emacs/set-up-history-movements-with-control {
  # For emacs editing mode
  ble-bind -m emacs -f C-up 'history-prev'
  ble-bind -m emacs -f C-down 'history-next'
}
blehook/eval-after-load keymap_emacs my/emacs/set-up-history-movements-with-control

function my/vi/set-up-history-movements-with-control {
  # For vi editing mode
  ble-bind -m vi_imap -f C-up 'history-prev'
  ble-bind -m vi_imap -f C-down 'history-next'
  ble-bind -m vi_nmap -f C-up 'vi-command/history-prev'
  ble-bind -m vi_nmap -f C-down 'vi-command/history-next'
}
blehook/eval-after-load keymap_vi my/vi/set-up-history-movements-with-control

Or you can also configure the same through the readline interface:

bind -m emacs '"\e[1;5A": previous-history'
bind -m emacs '"\e[1;5B": next-history'
bind -m vi-insert '"\e[1;5A": previous-history'
bind -m vi-insert '"\e[1;5B": next-history'
bind -m vi-command '"\e[1;5A": previous-history'
bind -m vi-command '"\e[1;5B": next-history'

[akinomyoga]

Yes. PageUp and PageDown are represented by prior and next as listed in a table in §3.1. These names are motivated by those in GNU Emacs.

[DJCrashdummy]

as i'm new to ble.sh and just figuring out what works for me and what does not, i was annoyed by the fact to lose the ability to browse through history - no matter how long the commands are - by just one key stroke.

after some research i found this and i'm pretty happy with it, as i guess i can work with C-up and C-down instead of just up and down compared to the original bash. and if you think about it a little bit more, it makes even more sense... thank you @akinomyoga for suggesting that!

that leads me to one question @akinomyoga: as C-up and C-down aren't used by default and using them to quickly browse the history seems pretty reasonable, why isn't that set by default?

---

BTW: i created a completely new $HOME/.blerc and just inserted

# For emacs editing mode
ble-bind -m emacs -f C-up 'history-prev'
ble-bind -m emacs -f C-down 'history-next'

# For vi editing mode
ble-bind -m vi_imap -f C-up 'history-prev'
ble-bind -m vi_imap -f C-down 'history-next'
ble-bind -m vi_nmap -f C-up 'vi-command/history-prev'
ble-bind -m vi_nmap -f C-down 'vi-command/history-next'

via copy & paste... but now every time i open a terminal, i get this:

ble-bind: Unknown ble edit function `vi-command/history-prev'.
ble-bind: Unknown ble edit function `vi-command/history-next'.

as i have no clue about vi or vim, i can't tell if this is expected... for sure everything is fine and still works if i comment resp. remove the vi lines.
i just found it somewhat odd, that 2 of the 4 vi lines produced an error, so i just wanted to mention that.

[akinomyoga]

via copy & paste... but now every time i open a terminal, i get this:

ble-bind: Unknown ble edit function `vi-command/history-prev'.
ble-bind: Unknown ble edit function `vi-command/history-next'.

as i have no clue about vi or vim, i can't tell if this is expected...

Ah, OK. As described in §6.3, to fully configure the Vim settings, they need to be executed through the "keymap_vi" load hook:

function my/vim-load-hook {
  # Put your vi editing mode settings here
  ble-bind -m vi_imap -f C-up 'history-prev'
  ble-bind -m vi_imap -f C-down 'history-next'
  ble-bind -m vi_nmap -f C-up 'vi-command/history-prev'
  ble-bind -m vi_nmap -f C-down 'vi-command/history-next'
}
blehook/eval-after-load keymap_vi my/vim-load-hook

i just found it somewhat odd, that 2 of the 4 vi lines produced an error, so i just wanted to mention that.

That is because history-{prev,next} are defined in the main ble.sh, while vi-command/history-{prev,next} is only defined in the keymap.vi module, whose loading is delayed. The keymap_vi load hook is used to run the configurations after loading the keymap.vi module.

[akinomyoga]

@DJCrashdummy I updated the code examples in my original reply #440 (comment). Thank you.

[DJCrashdummy]

That is because history-{prev,next} are defined in the main ble.sh, while vi-command/history-{prev,next} is only defined in the keymap.vi module, whose loading is delayed.

that makes sense... thank you for clarifying.

[akinomyoga]

@DJCrashdummy Let me create a separate thread because it is a related but separate discussion.

that leads me to one question @akinomyoga: as C-up and C-down aren't used by default and using them to quickly browse the history seems pretty reasonable, why isn't that set by default?

Hmm, that's actually a good question. I haven't cared about it and haven't noticed that C-up and C-down are unused. Come to think of it, yes, I don't have memory that I used C-up and C-down in Bash. I think we can bind it to these. I'll think about it.

[DJCrashdummy]

if it won't get the default, IMHO this should be added somewhere to the manual, Q&A, wiki or the like as i was pretty surprised to not even find a hint about that.

[akinomyoga]

In commit d7afee0, I added the default keybindings of C-up and C-down.

[DJCrashdummy]

though one additional and also somewhat related question @akinomyoga (which would make this feature for me personally perfect):
is it possible to prevent up and down from browsing the history at all? ...so that no matter what, C-up/C-down browses the history and up/down just the current command. this would make working with longer commands really convenient for me.

[akinomyoga]

For emacs and vi_imap, you can configure them by

# emacs
ble-bind -m 'emacs' -f 'up' 'backward-line'
ble-bind -m 'emacs' -f 'down' 'forward-line'

# vi_imap
ble-bind -m 'vi_imap' -f 'up' 'backward-line'
ble-bind -m 'vi_imap' -f 'down' 'forward-line'

It seems there aren't exactly corresponding widgets for vi_nmap. The corresponding widgets seem to hardcode the history option. In this case, you can define a modified version:

# vi_nmap
function ble/widget/my/vi_nmap/forward-line {
  local ARG FLAG REG; ble/keymap:vi/get-arg 1
  ble/widget/vi-command/relative-line.impl "$ARG" "$FLAG" "$REG"
}
function ble/widget/my/vi_nmap/backward-line {
  local ARG FLAG REG; ble/keymap:vi/get-arg 1
  ble/widget/vi-command/relative-line.impl "$((-ARG))" "$FLAG" "$REG"
}
ble-bind -m 'vi_nmap' -f 'up' 'my/vi_nmap/backward-line'
ble-bind -m 'vi_nmap' -f 'down' 'my/vi_nmap/forward-line'

I haven't actually tested the above settings, so could you confirm they work?

[DJCrashdummy]

thanks @akinomyoga for the quick reply!
i didn't think it was that easy, as the default binding for both up and down has just a closing history in it (ble-bind -m 'emacs' -f 'down' '... history') instead of history-prev resp. history-next. ...so i assumed that there is something hardcoded.

---

as i never used vi/vim, i have no clue how to work with it... i don't even know how i get form the "insert mode" to the "normal mode". 🤷
so unfortunately i can just confirm that in the emacs mode and the default vi insert mode (vi_imap) everything works as expected. 👍

[akinomyoga]

If you don't use the vi editing mode and don't know how to test it, that's fine. Thank you for checking the behavior with the emacs editing mode!

FYI, you can switch to the normal mode by pressing Escape, C-[, or C-c in the insert mode. If you want to come back to the insert mode, you can press i, a, or many other different commands with additional effects.