04-something-tuple-pattern.egi

--
-- Tuple pattern at a bare-variable matcher (paper Lemma "MS Progress",
-- tuple case).  The tuple pattern's structural index is product-headed,
-- so `something : Matcher b` fails the structural check b' <: (a' x b').
--
-- Expected: Type error (something vs a product-headed slot)
--

def t := matchAll (1, 2) as something with ($x, $y) -> x