Running once

Sometimes several tasks call the same helper, and it should only run once: one prompt, one download, one login. Mark it once: true. The first call runs it, and every later call gets the same values back without running it again:

tasks:
  _pick-category:
    once: true
    results: [CATEGORY]
    steps:
      - get:
          - CATEGORY:
              info: Which category?
              options: [history, science, music]

  ask-question:
    steps:
      - call: _pick-category
      - run: curl -s "https://the-trivia-api.com/v2/questions?limit=1&categories={{.CATEGORY}}"

  count-questions:
    steps:
      - call: _pick-category
      - run: curl -s https://the-trivia-api.com/v2/metadata

  morning:
    steps:
      - call: ask-question
      - call: count-questions

hobnob morning asks for a category once. When count-questions calls _pick-category, hobnob doesn't ask again. It prints the values the first run set instead:

call: [count-questions] _pick-category (cached — CATEGORY=history)

Running ask-question or count-questions on its own still asks, because each is then the first call.

What a later call gets

hobnob remembers every variable the first run ended with. A later call takes from those exactly what it would take from a real run: the task's results:, or whatever its own into: lists.

Rules

• once: belongs to the task, so it applies to every call, from anywhere, for as long as hobnob is running.
• A later call's with: is ignored. It gets the first run's values, even if it passes something different.
• A later call overwrites. If the caller changed CATEGORY since the first call, the next call puts the remembered value back. Only the values it brings back are touched.
• A task that skipped itself with if: is remembered as setting nothing, so every later call gets nothing back either.
• A failure under soft: true isn't remembered, so the next call runs the task again.