Subworkflows e.g. “macros”

In the previous tutorial, we listed all of the workflow steps in a single file. Alternatively, we can extract some of the steps into another workflow.

docs/tutorials/multistep3.wic 
steps:
- touch:
    in:
      filename: !ii empty.txt
- append_twice.wic:
- cat:

docs/tutorials/append_twice.wic

steps:
- append:
    in:
      str: !ii Hello
- append:
    in:
      str: !ii World!
docs/tutorials/multistep3.wic.gv.png

Multistep

We have simply moved the append steps into append_twice.wic and called it from the main workflow. As you can see from the arrows in the graphical representation, the exact same edges have been inferred! The inference algorithm is guaranteed to work identically across subworkflow boundaries! You are completely free to abstract away minor details behind a subworkflow, and the main workflow graph will be identical.