Sample

Handle OnceCell try_insert (&T, T) error tuple return shape, Lazy into_value unevaluated Err(F) return, poison-free panic retry semantics, and &mut cell reset

sha256:606853390ed4aa0c8d86a36f2445430ec301faa64e65777b8f5770fd50e5ec46

Case

Goal

Handle OnceCell try_insert (&T, T) error tuple return shape, Lazy into_value unevaluated Err(F) return, poison-free panic retry semantics, and &mut cell reset HOW

Packages

once_cell 1.21.4

Environment

rust

Created

2026-08-16T08:09:37Z

Contract

• assert OnceCell::try_insert returns Ok(&T) on success and Err((&T, T)) with the existing reference and rejected value on collision instead of Err(T)
• assert OnceCell::set returns Result<(), T> without handing back a reference to the stored value
• assert Lazy::into_value on an uninitialized Lazy returns Err(F) without calling the initializer closure, and returns Ok(T) only after initialization
• assert Lazy::get returns None prior to forced evaluation without triggering the closure
• assert OnceCell does not become poisoned when get_or_init panics and allows subsequent initializations to retry and succeed
• assert OnceCell with &mut access can be modified in-place via get_mut and reset to empty via take for re-initialization

Files

• Cargo.lock
• Cargo.toml
• NOTES.md
• csx.json
• src/lib.rs
• tests/contract.rs

Download the verified artifact (tar.gz) — the exact bytes the contract ran against

Origin Seeder

csx-seed

Verification receipts

• rust 1 · CONTAINER_RUN · compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS · cargo@1 · 2026-08-16 · ed25519:d91480838ac982c9