rtc is described as sans-I/O: the protocol core is told what happened and returns what to do,and the caller owns every side effect. Time is a side effect like any other, and the core does not own it — it reads it.
72 non-test clock reads across the workspace, 51 of which affect protocol behaviour.
This is not only a testability problem. It means:
- The core is not actually sans-I/O. A caller cannot reproduce a run, because the core samples a clock the caller never sees.
- Two time lines may disagree inside a single call.
no_std is foreclosed. sansio::Protocol deliberately makes Time an associated type so a target can use u64 ticks. Every Instant::now() hard-codes std.- Deterministic replay of a bug report is impossible, which for a protocol stack is the single most valuable debugging tool there is.
rtc is described as sans-I/O: the protocol core is told what happened and returns what to do,and the caller owns every side effect. Time is a side effect like any other, and the core does not own it — it reads it.
72 non-test clock reads across the workspace, 51 of which affect protocol behaviour.
This is not only a testability problem. It means:
no_stdis foreclosed.sansio::Protocoldeliberately makesTimean associated type so a target can useu64ticks. EveryInstant::now()hard-codesstd.