CristalCaveGem » LustreC

let rec semi_unify dim1 dim2 =

  let dim1 = repr dim1 in

  let dim2 = repr dim2 in

  if dim1.dim_id = dim2.dim_id then () else

  match dim1.dim_desc, dim2.dim_desc with

  | Dunivar, _

  | _      , Dunivar -> assert false

  | Dvar   , Dvar    ->

      if dim1.dim_id < dim2.dim_id

      then dim2.dim_desc <- Dlink dim1

      else dim1.dim_desc <- Dlink dim2

  | Dvar   , _  -> raise (Unify (dim1, dim2))

  | _      , Dvar when not (occurs dim2 dim1) ->

      dim2.dim_desc <- Dlink dim1

  | Dite(i1, t1, e1), Dite(i2, t2, e2) ->

      begin

        semi_unify i1 i2;

	semi_unify t1 t2;

	semi_unify e1 e2

      end

  | Dappl(f1, args1), Dappl(f2, args2) when f1 = f2 && List.length args1 = List.length args2 ->

      List.iter2 semi_unify args1 args2

  | Dbool b1, Dbool b2 when b1 = b2 -> ()

  | Dint i1 , Dint i2 when i1 = i2 -> ()

  | Dident id1, Dident id2 when id1 = id2 -> ()

  | _ -> raise (Unify (dim1, dim2))