-type version() :: binary().
-type requirement() :: binary() | any().
-type major() :: non_neg_integer().
-type minor() :: non_neg_integer().
-type patch() :: non_neg_integer().
-type pre() :: [binary() | non_neg_integer()].
-type build() :: binary() | undefined.
-type t() :: #{
               major => major() 
             , minor => minor() 
             , patch => patch()
             , pre   => pre()
             , build => build()}.