[kixelated]

Problem

rt.boolThen was the last runtime combinator that took a closure dropper, restating core's drops by hand. rt.thenSome did the same for its value.

Approach

library::from_mir takes bool's inherent methods too, so then and then_some lower from core's MIR into core/bool.ts, as #129 did Option's and Result's. Their mappings, discards and none_last entries, and both runtime functions are deleted.

rt.once stays: OnceCell::get_or_init still wraps a closure that Fn calls in it. Its only test was bool::then with a bound closure, so drops/once.rs gains one called and one uncalled bound closure through get_or_init. A mutation of rt.once that skips the drop after the call fails the task differential (243 differences).

Tests: just check and just test pass. Drops are checked against native Rust by the existing then/then_some cases in drops.rs, drops/closures.rs, nested.rs, shapes.rs, and iters.rs, including Option<Option<_>> and () payloads.

Bundle size: the codec's bench and Decoder bundles are unchanged, since neither reaches bool::then. Only the codec harness calls then_some, which is now thenSome$bool_u64. moq-net's translation (just ts moq) never calls either and still type-checks.

The merge from main also regenerates lang's dyns.ts snapshot, which #176 and #177 left stale on main.

Impact

• Translator output: bool::then and then_some calls become calls of then$bool_… and thenSome$bool_… from core/bool.ts.
• Runtime: rt.boolThen and rt.thenSome are removed. MIGRATE.md has an entry.
• Every inherent bool method in core now lowers from MIR, unstable ok_or/ok_or_else included, under the same &mut, unsafe, and wrapping-arithmetic refusals.

Alternatives

• Allowlisting only then and then_some. Rejected: Option and Result take their whole impl, and std_refused already guards each body.

Follow-ups

• None needed. rt.once has one consumer left, get_or_init, which lowers through the runtime because its body writes through UnsafeCell.

(written by Claude Opus 5.5)

🤖 Generated with Claude Code

[chatgpt-codex-connector]

Codex Review Summary

This comment shows the latest Codex review activity on this pull request.

Review	Status	Commit	Review trigger
📝 Code Review	✅ Completed 2026-10-28T16:59:17.239538Z	ab172e0	Manual request
🔒 Security Review	✅ Completed 2026-10-28T17:01:14.090868Z	ab172e0	Manual request

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[kixelated]

Automated review by review (OpenAI)

Reviewed commit: 1bacb03

No actionable bugs found. Lowering bool combinators through the existing core-MIR path is a sensible simplification over duplicating ownership/drop behavior in runtime helpers. Inspected the generated eager/lazy branches, captured-closure disposal (including Fn-to-FnOnce), nested Option/unit sentinels, migration notes, and the replacement OnceCell coverage for rt.once. Keeping that wrapper for its remaining consumer is justified.

Verification: static code and fixture inspection only. I did not run tests, translations, or bundle-size measurements; the reported results in the PR description are not independently verified.

[kixelated]

@codex review

(written by Claude Opus 5.5)

[chatgpt-codex-connector]

Codex Review: Didn't find any major issues. Another round soon, please!

Reviewed commit: ab172e0dd5

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[chatgpt-codex-connector]

🛡️ Codex Security Review · Automatically triggered

Security review completed. No security issues were found in this pull request.

Reviewed commit: ab172e0dd5

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[kixelated]

Landing at ab172e0, the head Codex reviewed with no findings; CI passed. bool::then and then_some lower from core's MIR, rt.boolThen and rt.thenSome are removed, and rt.once stays for get_or_init with new differential coverage. No open decisions.

(written by Claude Opus 5.5)