[V4] No template-template

[ConorWilliams]

Summary by CodeRabbit

• Refactor
  • Reorganized internal context architecture to use policy-based design patterns for improved flexibility
  • Simplified handle model to reduce type complexity while maintaining safety semantics
  • Streamlined container integration in worker contexts for cleaner API surface

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✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Commit unit tests in branch v4-aa-ctx-3

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Caution

Some comments are outside the diff and can’t be posted inline due to platform limitations.

⚠️ Outside diff range comments (1)

src/core/poly_context.cxx (1)

32-53: ⚠️ Potential issue | 🟡 Minor

Typo and now-dead post_error.

• Line 52: "re-introdcue" → "re-introduce".
• With poly_context::post commented out and post(...) also removed from derived_poly_context/mono_context (per the PR-wide refactor), nothing in the library now constructs or throws post_error. Since it's export-ed, it remains part of the public ABI/API but is orphan/dead until post() is re-introduced. Consider either removing it (and restoring it alongside post() later) or adding a short comment explaining it's retained for the TODO.

✏️ Proposed typo fix

-  // TODO: re-introdcue post API if/when we support auto/scheduling contexts.
+  // TODO: re-introduce post API if/when we support auto/scheduling contexts.
   // virtual void post([[maybe_unused]] sched_handle<poly_context> handle) { LF_THROW(post_error{}); }

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@src/core/poly_context.cxx` around lines 32 - 53, Fix the typo in the TODO
comment by changing "re-introdcue" to "re-introduce", and address the dead
exported type post_error: either remove the exported post_error type until
poly_context::post (and related post implementations in
derived_poly_context/mono_context) are restored, or keep post_error but add a
short clarifying comment above it stating it is intentionally retained for
future post() re-introduction and currently unused; ensure references to
post_error, poly_context::post, derived_poly_context, and mono_context are
mentioned in the comment so maintainers know why it remains exported.

🧹 Nitpick comments (1)

src/batteries/contexts.cxx (1)

49-49: Optional: propagate noexcept on derived_poly_context::push for consistency with mono_context::push.

mono_context::push (line 71) is noexcept(noexcept(m_container.push(handle))), but the final override here drops that. A virtual override is allowed to be more noexcept than the base (poly_context::push has no noexcept), and since the Deque policy's push is what actually determines throwability, mirroring mono_context avoids a false exception-edge for derived_poly_context.

♻️ Suggested tweak

-  constexpr void push(steal_handle<context_type> handle) final { m_container.push(handle); }
+  constexpr void push(steal_handle<context_type> handle) noexcept(noexcept(m_container.push(handle))) final {
+    m_container.push(handle);
+  }

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@src/batteries/contexts.cxx` at line 49, The override
derived_poly_context::push currently lacks a noexcept specifier and should
mirror mono_context::push's conditional noexcept to avoid weakening exception
guarantees; change derived_poly_context::push to be
noexcept(noexcept(m_container.push(handle))) so its exception specification is
determined by the underlying Deque's m_container.push, matching
mono_context::push and preventing a spurious exception edge.

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Outside diff comments:
In `@src/core/poly_context.cxx`:
- Around line 32-53: Fix the typo in the TODO comment by changing "re-introdcue"
to "re-introduce", and address the dead exported type post_error: either remove
the exported post_error type until poly_context::post (and related post
implementations in derived_poly_context/mono_context) are restored, or keep
post_error but add a short clarifying comment above it stating it is
intentionally retained for future post() re-introduction and currently unused;
ensure references to post_error, poly_context::post, derived_poly_context, and
mono_context are mentioned in the comment so maintainers know why it remains
exported.

---

Nitpick comments:
In `@src/batteries/contexts.cxx`:
- Line 49: The override derived_poly_context::push currently lacks a noexcept
specifier and should mirror mono_context::push's conditional noexcept to avoid
weakening exception guarantees; change derived_poly_context::push to be
noexcept(noexcept(m_container.push(handle))) so its exception specification is
determined by the underlying Deque's m_container.push, matching
mono_context::push and preventing a spurious exception edge.

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 48df51f3-df4d-41c1-a914-5dbb4e50e63f

📥 Commits

Reviewing files that changed from the base of the PR and between 143ba78 and 9b05b25.

📒 Files selected for processing (7)

• benchmark/src/libfork/fib.cpp
• src/batteries/adaptors.cxx
• src/batteries/contexts.cxx
• src/core/concepts/context.cxx
• src/core/handles.cxx
• src/core/poly_context.cxx
• src/schedulers/busy.cxx