given a Toop of N results, which all share a common Err type, either return a Toop of all the 'Ok' values, or the first Err.
4 element toop.
5 element toop.
6 element toop.
7 element toop.
8 element toop.
9 element toop.
10 element toop.
11 element toop.
12 element toop.
compose a result containing a function with a result containing a value.