TH\Maybe\Option\transpose

Transposes an Option of a Result into a Result of an Option.

None will be mapped to Ok(None). Some(Ok(_)) and Some(Err(_)) will be mapped to Ok(Some(_)) and Err(_).

use TH\Maybe\Result;

self::assertEq(Result\ok(Option\some(4)), Option\transpose(Option\some(Result\ok(4))));
self::assertEq(Result\err("meat"), Option\transpose(Option\some(Result\err("meat"))));
self::assertEq(Option\transpose(Option\none()), Result\ok(Option\none()));