The Preview window

The preview window here is what FZF provides; there’s not a lot of magic added to it except to use it imaginatively. You can use pretty much any code that uses {} etc.

Best example is this, but you will perhaps not appreciate it unless you are somewhat familiar with the todo.txt format.

A simple example of a trivial addition to the preview mode is when you type # and hit enter, you get to see the xxh128sum of the file also:

The code for that is one line in the command history file:

: key=# see file hash also        ; toggle_xsum

and this function in the config file:

function toggle_xsum
    set -l p $preview_cmd
    set -l x "test -f {} && xxh128sum {}|rg --color=always -o '^.{ 32}' ; "
    set p (string replace $x '' $p) || set p "$x$p"
    set preview_cmd $p
    true
end

Another example is git mode, which uses it to show git diff, git log, etc.