/usr/share/zsh/functions/Misc/zed is in zsh-common 5.0.7-5.
This file is owned by root:root, with mode 0o755.
The actual contents of the file can be viewed below.
| 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 | #!/bin/zsh
# zed
#
# No other shell could do this.
# Edit small files with the command line editor.
# Use ^X^W to save, ^C to abort.
# Option -f: edit shell functions.  (Also if called as fned.)
local var opt zed_file_name
# We do not want timeout while we are editing a file
integer TMOUT=0 okargs=1 fun bind
while getopts "fb" opt; do
  case $opt in
    (f)
    fun=1
    ;;
    (b)
    bind=1
    ;;
  esac
done
shift $(( OPTIND - 1 ))
[[ $0 = fned ]] && fun=1
(( bind )) && okargs=0
if (( $# != okargs )); then
    echo 'Usage:
zed filename
zed -f function
zed -b'
    return 1
fi
local curcontext=zed:::
zstyle -m ":completion:zed:*" insert-tab '*' ||
    zstyle ":completion:zed:*" insert-tab yes
if (( bind )) || ! bindkey -M zed >&/dev/null; then
  # Make the zed keymap a copy of the current main.
  bindkey -N zed main
  # Save the current main.  In zle widgets called from
  # zed we may want to set this temporally.
  bindkey -A main zed-normal-keymap
  # Assign some default keys.
  # Depending on your stty's, you may be able to use ^J as accept-line, else:
  # The following isn't useful if we are copying viins, but that's
  # a nicety.
  bindkey -M zed '^x^w' accept-line
  bindkey -M zed '^M' self-insert-unmeta
  # Make zed-set-file-name available.
  # Assume it's in fpath; there's no error at this point if it isn't
  autoload -Uz zed-set-file-name
  zle -N zed-set-file-name
fi
if (( bind )) || ! bindkey -M zed-vicmd >&/dev/null; then
  bindkey -N zed-vicmd vicmd
  bindkey -M zed-vicmd "ZZ" accept-line
fi
(( bind )) && return 0
# don't mangle !'s
setopt localoptions nobanghist
if ((fun)) then
  var="$(functions $1)"
  # If function is undefined but autoloadable, load it
  if [[ $var = *\#\ undefined* ]] then
    var="$(autoload +X $1; functions $1)"
  elif [[ -z $var ]] then
    var="$1() {
}"
  fi
  vared -M zed -m zed-vicmd var && eval function "$var"
else
  zed_file_name=$1
  [[ -f $1 ]] && var="$(<$1)"
  while vared -M zed -m zed-vicmd var
  do
    {
      print -r -- "$var" >| $zed_file_name
    } always {
      (( TRY_BLOCK_ERROR = 0 ))
    } && break
    echo -n -e '\a'
  done
fi
return 0
# End of zed
 |