raw_match_type
  : hol_type -> hol_type ->
    (hol_type,hol_type) subst * hol_type list ->
    (hol_type,hol_type) subst * hol_type list
- val res1 = raw_match_type alpha  (alpha --> bool) ([],[]);
> val it = ([{redex = `:'a`, residue = `:'a -> bool`}], []) : ...
- raw_match_type (alpha --> beta --> gamma)
                 ((alpha --> bool) --> beta --> ind) res1;
> val it =([{redex = `:'c`, residue = `:ind`},
            {redex = `:'a`, residue = `:'a -> bool`}], [`:'b`]) : ....