If so, I feel like this would break consistency with the current syntax since e.g. all these definitions of `f` would be valid but have completely different type/meaning (even though in "classical" Haskell they would be identical):

  f x y = infix (+) 1 2 x y -- f :: Int -> Int -> Int
  f x   = infix (+) 1 2 x   -- f :: Int -> Int
  f     = infix (+) 1 2     -- f :: Int

I like the general idea to represent variable argument functions as infix function applications, but I wouldn't like a purely syntactical solution that adds no real new functionality and is biased towards non-function values like strings, integeres, etc.