oh-my-fish/plugins/emacs/emacs.load

function __major_version
  if test -n "$argv"
    set -l full_metadata (eval $argv --version)
    set -l full_version (echo $full_metadata | grep -o "[0-9]\+.[0-9]\+.[0-9]\+.[0-9]\+")
    set -l major_version (echo $full_version | sed  "s/\..*//")
  end

  echo $major_version
end

function __set_editor
  if not set -q EDITOR
    set -gx EDITOR emacs
  end
end

function __add_functions_to_path
  set emacs_functions $fish_path/plugins/emacs/functions
  set fish_function_path $emacs_functions $fish_function_path
end

if not set -q __emacs
  set __emacs (which emacs)
end
if not set -q __emacs_version
  set __emacs_version (__major_version $__emacs)
end

if test "$__emacs_version" -gt 23
  __set_editor
  __add_functions_to_path
end

set -e emacs
set -e emacs_version
functions -e __major_version
functions -e __plugins_path
functions -e __set_editor
functions -e __add_functions_to_path