I do much of my work from tmux, I love it so much that I want to setup some functionality that puts me in tmux even if I didnt ask for it.

Bash Function

Bash function to check if the shell is in a tmux session.

in_tmux () {
  if [ -n "$TMUX" ]; then
    return 0
  else
    return 1
  fi
  }

Using the bash function

I often open up vim to do some quick edits, but before I know it I have several splits open and I need access to another shell utility, but I forgot to start in tmux. This function makes sure that I start in tmux every time.

Using if_tmux to ensure vim is opened in tmux.

vim () { 
  in_tmux \
    && nvim \
    || bash -c "\
    tmux new-session -d;\
    tmux send-keys nvim Space +GFiles C-m;\
    tmux -2 attach-session -d;
    "
  }

I am not quite sure if this is proper use of the && and ||, let me know if you have a better way to do one thing if in_tmux returns true and another if it returns faslse.