Writing
Purpose
What a member wrote — the message's content in the clear. A writing exists only on a member's
device: before sealing on the sender's side, and after unsealing on a reader's. It never rests in a
store and never crosses a port; the moment it travels, it travels sealed. Keeping the writing a
named value keeps that boundary visible — everything that holds a Writing is, by that fact, on a
device.
Attributes
- text: is
Textthat carries the written text
Invariants
- The text is not empty — a message says something.
Scenarios
A writing carries its text
Given: the text "The hearing moved to Thursday." When: a Writing is created Then: it is accepted and reads back with that text
An empty writing is rejected
Given: an empty text When: a Writing is created Then: the creation is rejected because a message says something