[ryansolid]

The check

GUESS_WHILE_LOADING (spec 06 AC-3a) is Solid's OPTIMISTIC_WRITE_WHILE_LOADING (solidjs/solid#4795, #4797) at compile time.

What goes wrong. While x loads a new question, a guess on it composes on the previous answer. When the new answer lands it replaces the guess (D-34), so the user's change disappears while its action is still out.

When it fires. A handler guesses x and x's question reads something the click reads. The guess can be in the handler, an inferred or inline action, or a named action the handler calls. What the click reads is a selection or a row, for example.

When it doesn't. The handler is covered as in R-8:

• the element sits inside x's loading region; or
• the element is disabled on x; or
• for a form's onSubmit, every submit button is disabled on x.

The message offers Solid's repairs. The check follows the principle that a write must not read stale state.

Evidence from round 12:

• It flags 8 handlers in 5 .rx apps. A browser probe (select an issue, then rename or post while it loads) loses the change in every flagged app and in none of the unflagged ones. The probe is in eval/results/desk12-2026-11-11/repro/.
• It also fired on the eval's own references and on examples/ai/feed.rx. Those now disable the control while its value loads. Every reference still passes all its visible, hidden and overlap tests.

Checks run:

• cargo test passes, including the diagnostics page and a new unit test.
• ref npm run crate: the crate agrees with ref on all 351 programs.
• ref npm test passes.
• ref npm run compiled: 4 fails, the same 4 as on the branch without this change.

Also on this branch

Eval:

• XState arm, and the XState side-check results.
• Round 12: frozen pre-registration and results in eval/results/desk12-2026-11-11. Two Solid bugs traced, #4786 and #4787. Includes the plain-Solid repro for #4795.

Guide:

• A guide line on guessing a prop.
• "Guess only on a value that is shown", in general wording, following the #4795 ruling.

---

Generated by Claude Code

[socket-security]

Review the following changes in direct dependencies. Learn more about Socket for GitHub.

Diff	Package	Supply Chain Security	Vulnerability	Quality	Maintenance	License
	npm/​@​xstate/​react@​6.1.0
	npm/​xstate@​5.32.6

View full report