Cat alternatives for writing terminal input to file?

Question

When I want to quickly write something to a file that either get's pasted or manually input from the terminal, a quick cat > something.txt and Ctrl+D to close, is a nice shortcut. However of course this does not allow you to move the cursor around in case there is a glaring error, so your stuck opening a text editor such as vim or nano. However these take up your screen unless you use a terminal muxer and it's slightly inconvenient/overkill for my use case. Is there an alternative to cat that allows you to move the cursor? Some kind of micro editor that doesn't grab your screen and is literally just a text buffer until you Ctrl+D it?

My greater use case is I made a little helper script so I can type hel SomeScript in a terminal and it will automatically make a script with that name in my ~/bin which is in my path, add the shebang to the top, and chmod+x when I'm done. I used cat > ~/bin/$1 to start and decided I would make too many mistakes and switched to nano, but since it grabs the screen I can't see what I've been doing in the terminal prior to that without scrolling back and also I keep trying to use vim keys since I'm in an editor lol.

Answer 1

With rlwrap

rlwrap cat

If you configured readline properly (via ~/.inputrc), rlwrap would use the same key bindings as bash and other programs using readline.

With vi

If you're used to modal vi keybindings, there's also the "open mode" of the vi editor (The real vi, not some inadequate clone like vim or nvi).

With zsh

zsh command-line editing interface is also able to do multi-line without taking over the whole screen.

Here is an "implementation" of a quick editor, using zsh's vared builtin (whose purpose is to edit variables):

# in .zshrc
bindkey -N for-qe emacs
bindkey -M for-qe \
   "^M" self-insert-unmeta \
   "^J" self-insert-unmeta \
   "^X" accept-line
qe(){
    local e=$(cat $1; echo x); e=${e%x}
    vared -M for-qe e && printf %s $e > $1
}

# usage
% qe some_file
  # Enter, ^M, ^J = insert a newline
  # ^X = save & exit
  # ^C = abort editing 

Answer 2

If you want to stick to your "quick" method and do not want to learn ed you could use:

cat > test <<'EOF'
...
EOF

This is no complete editor, of course, but could edit the line you are typing (before pressing enter).