a vim script for detecting the language of a text file and setting the spelling language automatically.

detect_lang.vim

if (exists("g:loaded_detect_lang") && g:detect_lang) || &cp
		finish
endif

let g:detect_lang = 1

command! DetectLanguage exec('py detect_language()')
command! SetSpellLang exec('py detect_and_set_spelllang()')

python <<EOF
from glanguage import Translator
import vim

def detect_buffer_language():
	t = Translator()
	return t.detect(unicode(vim.current.buffer[0:3]))

def detect_language():
	print detect_buffer_language().lang

def detect_and_set_spelllang():
	l = detect_buffer_language()
	print "Document language is " + l.lang
	vim.command("set spell")
	vim.command("set spelllang=" + l.lang_code)
EOF