The Pipeline Framework

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Aspect Ordering & Precedence Rules ​

Ordering Rules ​

  1. Aspects are applied in ascending order - Aspects with lower order values are applied before aspects with higher order values.

  2. Lower order executes closer to the step boundary - When aspects are chained around a step, those with lower order values are positioned closer to the actual step execution.

  3. Same position chaining - If multiple aspects target the same position (BEFORE_STEP or AFTER_STEP), they execute in order (lower order values closest to the step).

  4. Default order is 0 - If no order is specified, aspects default to order 0.

  5. Tie-breaking - When multiple aspects share the same order and position, execution order is deterministic but unspecified; implementations MUST preserve declaration order.

  6. Order is signed - Order is a signed integer. Negative values are allowed and execute before zero-valued aspects.

  7. Position precedence - BEFORE_STEP aspects always execute before the step, and AFTER_STEP aspects always execute after the step, regardless of order value.

Example ​

Consider these aspects applied to a single step:

  • Aspect A: position=BEFORE_STEP, order=10
  • Aspect B: position=BEFORE_STEP, order=5
  • Aspect C: position=AFTER_STEP, order=0
  • Aspect D: position=AFTER_STEP, order=1

The execution order would be:

  1. Aspect A executes (BEFORE_STEP, farthest from step)
  2. Aspect B executes (BEFORE_STEP, closest to step)
  3. Actual step executes
  4. Aspect D executes (AFTER_STEP, closest to step)
  5. Aspect C executes (AFTER_STEP, farthest from step)

This creates the following logical pipeline:

Input -> Aspect A -> Aspect B -> Step -> Aspect D -> Aspect C -> Output