I would simplify that to x = foo() ||| <error case> <happy case> (With the specific symbol used in lieu of ||| to be decided) That is shorter and keeps t

I would simplify that to x = foo() ||| <error case> <happy case> (With the specific symbol used in lieu of ||| to be decided) That is shorter and keeps the happy path unindented, even if it has additional such constructs, for example x = foo() ||| return Error(err, “foo failed”) y = bar() ||| return Error(err, “bar failed”)