I assume you mean the Go part. I meant to write a mini-blog post but can summarize here. Lets say we want to use an Either<ok, error> and chain computations. In Go naively without generics this needs the product no-of-input-types x no-of-output-types forms of result mappers/chainers. Instead we make functions that bind all it's inputs so only has an output-type. Now we only need linearly as many mappers/chainers (and_then's). e.g.

  x, err := computeAThing(1, 1)
  y, err := and_then.Int(err, makeComputeAThingFn(x, 1))
  z, err := and_then.Int(err, makeComputeAthingFn(x, y))
  another, err := and_then.AnotherType(err, makeComputeAnotherTypeFn(z))

where makeComputeAThingFn(...) returns a function with the body `return computeAThing(...)`. `err` will end up with the first non-nil error and the following and_then.X's will be no-ops.