zshでCommandNotFoundにhookするスクリプトできたよー＾O＾ノ

.zshrc

preexec () {
  [[ -z "`whence ${1%% *}`" ]] && echo "NOTFOUND!!! ${1%% *}"                                          
}

# ---- #

preexec () {
  cmd=${1%% *}
  if [ -z "`whence ${cmd}`" ]; then
    if [ $cmd = 'yabai' ]; then
      arg=${1##* }                                                          
      echo "$arg is YABAI"
    fi
  fi
}

# 
# $ yabai a
# a is YABAI
# zsh: command not found: yabai
#