scriptencoding utf-8
let s:save_cpo = &cpo
set cpo&vim


let s:prefix = expand("<sfile>:p:h:h:t")
function! s:set_prefix(prefix)
	let s:prefix = a:prefix
endfunction


let s:uniq_counter = 0
function! s:make_uniq_nr()
	let s:uniq_counter += 1
	return s:uniq_counter
endfunction


function! s:numbering(...)
	let tabnr = get(a:, 1, tabpagenr())
	let uniq_nr = s:make_uniq_nr()
	call settabvar(tabnr, s:prefix . "_gift_uniq_tabpagenr", uniq_nr)
	return uniq_nr
endfunction


function! s:uniq_nr(...)
	let tabnr = get(a:, 1, tabpagenr())
	let uniq_nr = gettabvar(tabnr, s:prefix . "_gift_uniq_tabpagenr", -1)
	if uniq_nr == -1
		let uniq_nr = s:numbering(tabnr)
	endif
	return uniq_nr
endfunction


let &cpo = s:save_cpo
unlet s:save_cpo