mytheclipse/.hermes/plans/mytheclipse-round21-spec.md

Implementation Spec: Round 21 — CPU Parallel Compute Primitives

Goal

Fitur parallel khusus CPU (rayon) yang bounded, panic-isolated, error-aggregated. Melengkapi compute() (single call) dengan batch parallel + fork-join.

New API (crates/mytheclipse/src/compute.rs, feature compute)

1. compute_map<I, T, F>(items, f) -> Result<Vec<T>, ComputeErrors>

• pack_items di rayon compute pool: par_iter().map(f) — bounded concurrency otomatis (rayon work-stealing sizing = CPU cores), ordered output.
• f: Fn(I::Item) -> Result<T, ComputeMapItemError>:
  • item error string → dikumpulkan
  • panic per item di-catch (catch_unwind) → jadi error, pool survive
• ComputeErrors { errors: Vec<String> } — Display, Error, len, is_empty. (Tidak pakai AggregateError — feature compute harus compile tanpa resiliency.)
• I: IntoParallelIterator (rayon) — work langsung di pool, tanpa materialize.

2. compute_join<A, B, RA, RB>(a, b) -> Result<(RA, RB), MytheclipseError>

• rayon::join wrapper di compute pool: 2 heavy closures run parallel.
• Panic-isolated (catch_unwind per branch) — pool survive, error jadi ComputePanic.

3. compute_par_for_each<I>(items, f) -> Result<(), ComputeErrors>

• par_iter().for_each idiom — fire side-effects parallel di pool.
• Panic isolation per item.

Design notes

• Reuse context().compute_pool (existing sizing: compute_threads dari RuntimeConfig / available_parallelism) — konsisten dengan compute().
• rayon::ThreadPool::install untuk semua — force run di pool.
• Panic isolation: std::panic::catch_unwind + AssertUnwindSafe per item (sama seperti compute() yang sudah proven).
• Bounded = rayon work-stealing — concurrency = pool threads (CPU cores), bukan item count. Tidak perlu semaphore.

Files

• crates/mytheclipse/src/compute.rs (3 fungsi + error type)
• crates/mytheclipse/src/lib.rs (export)
• doctests: compute_map, compute_join, compute_par_for_each
• tests: unit di compute.rs

Verification

1. cargo build --workspace --all-features — exit 0
2. cargo test -p mytheclipse compute --all-features — 0 FAILED
3. cargo test -p mytheclipse --doc --all-features — 0 FAILED
4. cargo clippy --workspace --all-features — 0 new
5. spec + commit + push