Pattern for modifying workflows using map and reduce?

[SimonHeybrock]

Context

Using Sciline's (Cycleban's) map/reduce we modify workflows. See scipp/esssans#135 and scipp/esssans#135 (comment) for an example. The use of helper functions is not great UX (example: workflow = sans.with_banks(workflow, banks=[...])).

We should gain some more experience and get "data" on how well this works, then consider the alternatives below (or find more alternatives)

Alternatives

• Make this arguments of the workflow creation, LokiWorkflow(sample_runs=..., ...).
• Turn LokiWorkflow into a builder (using builder pattern):

  workflow = LokiWorkflow()
  workflow.set_sample_runs([...])
  workflow.build()  # or build automatically in `workflow.compute()`, by making this a wrapper.

• Turn LokiWorkflow into a wrapper, with internal reference to the pipeline. Dedicated methods can set and update the internal workflow.