Sample
collection 1.19.1: Extract or iterate elements from package:collection PriorityQueue in priority order without mutating the queue
Verified sample for pub collection 1.19.1: Extract or iterate elements from package:collection PriorityQueue in priority order without mutating the queue.…
sha256:8376217b4f599376ba9a7e40e78691ee88b2b13e999166fe688cf065e655bbc3
This network offers one thing: a sample that builds. It ran the sample in a sandbox and kept the signed receipt. It grades nothing and warrants nothing — whether the same code builds where you are is not something it measured.
How many distinct signing keys filed a passing contract receipt. One is the author alone; more than one means somebody else built it too. A key is self-generated with nothing registered behind it, so it counts keys, not people.
MIT-0
Execution evidence
The declared environment and the signed runs are kept apart, so you can see exactly what this sample ran and where.
- Evidence basis
- Signed contract pass
- Verification receipts
- 2
- Signing keys that built it
- 2
Declared environment
dart linux x64 dart dart pub
Verification-run environments
| Environment | Contract | Stages | Run |
|---|---|---|---|
| dart 3 · linux debian/x64 · docker ed25519:d91480838ac982c9 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · pub@1 |
2026-08-17 |
| dart 3 · linux debian/x64 · docker ed25519:2175b912ea1c23b1 | PASS | compile:SKIPPED · contract:PASS · load:PASS · resolve:PASS CONTAINER_RUN · pub@1 |
2026-08-18 |
Case
HOW- Goal
- Extract or iterate elements from package:collection PriorityQueue in priority order without mutating the queue
- Packages
- Symbols
-
- PriorityQueue
- HeapPriorityQueue
- Environment
- dart
- Created
- 2026-08-17T03:53:33Z
Contract
- PriorityQueue does not implement Iterable, and HeapPriorityQueue.unorderedElements yields elements in internal binary heap storage order rather than priority-sorted order.
- Extracting elements in priority-sorted order requires calling removeFirst, which mutates and drains the queue unless performed on a copy.
- Mutating an element's priority field in-place does not re-heapify HeapPriorityQueue, causing removeFirst to yield stale minimums.
Files
- NOTES.md
- csx.json
- lib/priority_queue_trap.dart
- pubspec.lock
- pubspec.yaml
- test/contract.dart