src/hope_result.erl

   1 -module(hope_result).
   2
   3
   4 -export_type(
   5     [ t/2
   6     ]).
   7
   8 -export(
   9     [ pipe/2
  10     ]).
  11
  12
  13 -type t(A, B) ::
  14       {ok, A}
  15     | {error, B}
  16     .
  17
  18
  19 -spec pipe([F], X) ->
  20     t(Ok, Error)
  21     when X     :: any()
  22        , Ok    :: any()
  23        , Error :: any()
  24        , F     :: fun((X) -> t(Ok, Error))
  25        .
  26 pipe([]    , X) -> X;
  27 pipe([F|Fs], X) ->
  28     case F(X)
  29     of  {error, _}=E -> E
  30     ;   {ok, Y}      -> pipe(Fs, Y)
  31     end.