node id (a: bool) returns (o: bool);
let
  o = a;
tel

node test_merge_tuples (a, b: bool) returns (o: bool);
var t: bool;
let
  (o, t) = if a and b then (true, false) else (false, true);
tel

node my_and (a, b: bool) returns (o: bool);
let
  o = if a then b else id(false -> a);
tel