Change Alternative instance

[chshersh]

Current implementation:

trial/trial/src/Trial.hs

Lines 298 to 301 in 49ad9a0

	(<|>) :: Trial e a -> Trial e a -> Trial e a
	r@Result{} <|> _ = r
	_ <|> r@Result{} = r
	(Fiasco e1) <|> (Fiasco e2) = Fiasco (e1 <> e2)

Proposal:

    (<|>) :: Trial e a -> Trial e a -> Trial e a
    r@Result{}  <|> _           = r
    f@Fiasco{}  <|> r@Result{}  = f <> r
    (Fiasco e1) <|> (Fiasco e2) = Fiasco (e1 <> e2)

New semantics: return first Result, but also accumulate all previous Fiascos.

[vrom911]

Let's first check is the new semantic would preserve all the laws. If not we still can add such function as I see how useful it could be sometimes 🙂