For reading more about Railway Oriented Programming, look here.
It's easy to construct reusable chains, with stateless functions and even (to some extent) graphs of functionalities.
It's nontheorical essence is:
________ ________ ________
happy path --->| |--->| |--->| |---> result
| func | | func | | func |
failure --->| |--->| |--->| |---> error
-------- -------- --------
As you see it looks like the idiomatic Go pattern of writing functions as func(TIn) (TOut, error), except for the input error from previous step.
A sequential chain of functions can be made like:
c := Chain(nil, step1, step2, step3)
res := c(Result{...})Status: WIP; there are v1 and v2 branches, but it's being redesigned to more closely resembles Go's middleware pattern. For example now we can handle panics as we do in web apps.