/**
* @brief Is the character a Thai character?
*/
int th_isthai(thchar_t c) { return th_istis(c) && ((c) & 0x80); }
static VALUE
f_th_istis(VALUE obj, VALUE ch)
{
/* FIXME: a range must be checked? */;
return (th_istis(NUM2UINT(ch)) ? Qtrue : Qfalse);
}