s[regex]<ret>, but not
Add the following mapping to your kakrc and try
s<a-i>w to select all words.
map -docstring 'Split object' global prompt <a-i> '<esc>: enter-user-mode split-object<ret>'
You need split-object.kak to have it working.
I previously had it mapped on
<a-I> from the normal mode, but it feels more satisfying to have it on the
Got the idea from @gustavo-hms on his recent post.