'Returns an ordered list of (ver, name) for the given lang.'

def vers_and_names_from_lang(self, lang):

    vers_and_names = self._vers_and_names_from_lang.get(lang)
    if (vers_and_names is None):
        cix_glob = join(self.stdlibs_dir, (safe_lang_from_lang(lang) + '*.cix'))
        cix_paths = glob(cix_glob)
        vers_and_names = []
        for cix_path in cix_paths:
            name = splitext(basename(cix_path))[0]
            if ('-' in name):
                (base, ver_str) = name.split('-', 1)
                ver = _ver_from_ver_str(ver_str)
            else:
                base = name
                ver = None
            if (base.lower() != lang.lower()):
                continue
            vers_and_names.append((ver, name))
        vers_and_names.sort()
        self._vers_and_names_from_lang[lang] = vers_and_names
    return vers_and_names
