fsl.tools
// Patterns r06

Acyclic flow

A one-way pipeline with a terminal state. Once you've shipped, you've shipped — there's no going back.

Code

order.fsl
const order = sm`
  cart     'checkout'   paying;
  paying   'authorize'  packed;
  packed   'ship'       shipped;
  shipped  'deliver'    delivered;
`;

// no edge leaves `delivered` — terminal by construction.

Notes

Audit the receipts later by walking the hook log; you'll never see a delivered order rewind, because there's no syntax for it.