{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2025:OCKPM3YZA5LRQLPHTHMAHHNO3L","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"3d047d7f38a7c4856ba86bf34bd244299b36ea25bf496a0a7875ccac1441f736","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.PL","submitted_at":"2025-06-25T12:11:47Z","title_canon_sha256":"886c0c54a4cf71f62ba1ca91789dab5e4224b406f384b325fc2daaa836e168d0"},"schema_version":"1.0","source":{"id":"2506.20356","kind":"arxiv","version":4}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2506.20356","created_at":"2026-06-08T01:05:01Z"},{"alias_kind":"arxiv_version","alias_value":"2506.20356v4","created_at":"2026-06-08T01:05:01Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2506.20356","created_at":"2026-06-08T01:05:01Z"},{"alias_kind":"pith_short_12","alias_value":"OCKPM3YZA5LR","created_at":"2026-06-08T01:05:01Z"},{"alias_kind":"pith_short_16","alias_value":"OCKPM3YZA5LRQLPH","created_at":"2026-06-08T01:05:01Z"},{"alias_kind":"pith_short_8","alias_value":"OCKPM3YZ","created_at":"2026-06-08T01:05:01Z"}],"graph_snapshots":[{"event_id":"sha256:45068810f5645c9d081f20d8ffdbd3e9edc4ddc76f81b033329ccf59b836cfcc","target":"graph","created_at":"2026-06-08T01:05:01Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2506.20356/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"We tackle the problem of statically ensuring that message-passing programs never run into deadlocks. We focus on concurrent functional programs governed by context-free session types, which can express rich tree-like structures not expressible in standard session types. We propose a new type system based on context-free session types: it enforces both protocol conformance and deadlock freedom, also for programs implementing cyclic communication topologies with recursion and polymorphism. We show how the priority-based approach to deadlock freedom can be extended to this expressive setting. We ","authors_text":"Andreia Mordido, Jorge A. P\\'erez","cross_cats":[],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.PL","submitted_at":"2025-06-25T12:11:47Z","title":"Deadlock-free Context-free Session Types"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2506.20356","kind":"arxiv","version":4},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:bfbc44652575891fbda975a657d1a35efdaebd54f2d8d9eaa57a4406e40bb52c","target":"record","created_at":"2026-06-08T01:05:01Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"3d047d7f38a7c4856ba86bf34bd244299b36ea25bf496a0a7875ccac1441f736","cross_cats_sorted":[],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.PL","submitted_at":"2025-06-25T12:11:47Z","title_canon_sha256":"886c0c54a4cf71f62ba1ca91789dab5e4224b406f384b325fc2daaa836e168d0"},"schema_version":"1.0","source":{"id":"2506.20356","kind":"arxiv","version":4}},"canonical_sha256":"7094f66f190757182de799d8039daedacedae5daf6da01d781564abd896e16bd","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"7094f66f190757182de799d8039daedacedae5daf6da01d781564abd896e16bd","first_computed_at":"2026-06-08T01:05:01.242079Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-06-08T01:05:01.242079Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"ukoVuHNc8s+UsuYfqTWzazbb6RsXVRinCars8DsSgXoloyXu/glWO1eb6I+97e+DAiEy2AeSdDoUxSPMWq42Bw==","signature_status":"signed_v1","signed_at":"2026-06-08T01:05:01.243300Z","signed_message":"canonical_sha256_bytes"},"source_id":"2506.20356","source_kind":"arxiv","source_version":4}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:bfbc44652575891fbda975a657d1a35efdaebd54f2d8d9eaa57a4406e40bb52c","sha256:45068810f5645c9d081f20d8ffdbd3e9edc4ddc76f81b033329ccf59b836cfcc"],"state_sha256":"59241903f32ed6c8715b6c4a74f77dc7a8ca286d645286c9807e81705e4e391d"}