7 Search Results for "Tirore, Dawit"

Document
DOI: 10.4230/LIPIcs.ITP.2025.13
Barendregt’s Theory of the λ-Calculus, Refreshed and Formalized

Authors: Adrienne Lancelot, Beniamino Accattoli, and Maxime Vemclefs

Published in: LIPIcs, Volume 352, 16th International Conference on Interactive Theorem Proving (ITP 2025)

Abstract
Barendregt’s book on the untyped λ-calculus refines the inconsistent view of β-divergence as representation of the undefined via the key concept of head reduction. In this paper, we put together recent revisitations of some key theorems laid out in Barendregt’s book, and we formalize them in the Abella proof assistant. Our work provides a compact and refreshed presentation of the core of the book. The formalization faithfully mimics pen-and-paper proofs. Two interesting aspects are the manipulation of contexts for the study of contextual equivalence and a formal alternative to the informal trick at work in Takahashi’s proof of the genericity lemma. As a by-product, we obtain an alternative definition of contextual equivalence that does not mention contexts.
Cite as

Adrienne Lancelot, Beniamino Accattoli, and Maxime Vemclefs. Barendregt’s Theory of the λ-Calculus, Refreshed and Formalized. In 16th International Conference on Interactive Theorem Proving (ITP 2025). Leibniz International Proceedings in Informatics (LIPIcs), Volume 352, pp. 13:1-13:22, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2025)

Copy BibTex To Clipboard

@InProceedings{lancelot_et_al:LIPIcs.ITP.2025.13,
  author =	{Lancelot, Adrienne and Accattoli, Beniamino and Vemclefs, Maxime},
  title =	{{Barendregt’s Theory of the \lambda-Calculus, Refreshed and Formalized}},
  booktitle =	{16th International Conference on Interactive Theorem Proving (ITP 2025)},
  pages =	{13:1--13:22},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-396-6},
  ISSN =	{1868-8969},
  year =	{2025},
  volume =	{352},
  editor =	{Forster, Yannick and Keller, Chantal},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ITP.2025.13},
  URN =		{urn:nbn:de:0030-drops-246114},
  doi =		{10.4230/LIPIcs.ITP.2025.13},
  annote =	{Keywords: lambda-calculus, head reduction, equational theory}
}
Document
DOI: 10.4230/LIPIcs.ITP.2025.11
Animating MRBNFs: Truly Modular Binding-Aware Datatypes in Isabelle/HOL

Authors: Jan van Brügge, Andrei Popescu, and Dmitriy Traytel

Published in: LIPIcs, Volume 352, 16th International Conference on Interactive Theorem Proving (ITP 2025)

Abstract
Nominal Isabelle provides powerful tools for meta-theoretic reasoning about syntax of logics or programming languages, in which variables are bound. It has been instrumental to major verification successes, such as Gödel’s incompleteness theorems. However, the existing tooling is not compositional. In particular, it does not support nested recursion, linear binding patterns, or infinitely branching syntax. These limitations are fundamental in the way nominal datatypes and functions on them are constructed within Nominal Isabelle. Taking advantage of recent theoretical advancements that overcome these limitations through a modular approach using the concept of map-restricted bounded natural functor (MRBNF), we develop and implement a new definitional package for binding-aware datatypes in Isabelle/HOL, called MrBNF. We describe the journey from the user specification to the end-product types, constants and theorems the tool generates. We validate MrBNF in two formalization case studies that so far were out of reach of nominal approaches: (1) Mazza’s isomorphism between the finitary and the infinitary affine λ-calculus, and (2) the POPLmark 2B challenge, which involves non-free binders for linear pattern matching.
Cite as

Jan van Brügge, Andrei Popescu, and Dmitriy Traytel. Animating MRBNFs: Truly Modular Binding-Aware Datatypes in Isabelle/HOL. In 16th International Conference on Interactive Theorem Proving (ITP 2025). Leibniz International Proceedings in Informatics (LIPIcs), Volume 352, pp. 11:1-11:20, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2025)

Copy BibTex To Clipboard

@InProceedings{vanbrugge_et_al:LIPIcs.ITP.2025.11,
  author =	{van Br\"{u}gge, Jan and Popescu, Andrei and Traytel, Dmitriy},
  title =	{{Animating MRBNFs: Truly Modular Binding-Aware Datatypes in Isabelle/HOL}},
  booktitle =	{16th International Conference on Interactive Theorem Proving (ITP 2025)},
  pages =	{11:1--11:20},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-396-6},
  ISSN =	{1868-8969},
  year =	{2025},
  volume =	{352},
  editor =	{Forster, Yannick and Keller, Chantal},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ITP.2025.11},
  URN =		{urn:nbn:de:0030-drops-246091},
  doi =		{10.4230/LIPIcs.ITP.2025.11},
  annote =	{Keywords: syntax with bindings, datatypes, inductive predicates, Isabelle/HOL}
}
Document
DOI: 10.4230/LIPIcs.ITP.2025.15
Certified Implementability of Global Multiparty Protocols

Authors: Elaine Li and Thomas Wies

Published in: LIPIcs, Volume 352, 16th International Conference on Interactive Theorem Proving (ITP 2025)

Abstract
Implementability is the decision problem at the heart of top-down approaches to protocol verification. In this paper, we present a mechanization of a recently proposed precise implementability characterization by Li et al. for a large class of protocols that subsumes many existing formalisms in the literature. Our protocols and implementations model asynchronous commmunication, and can exhibit infinite behavior. We improve upon their pen-and-paper results by unifying distinct formalisms, simplifying existing proof arguments, elaborating on the construction of canonical implementations, and even uncovering a subtle bug in the semantics for infinite words. As a corollary of our mechanization, we show that the original characterization of implementability applies even to protocols with infinitely many participants. We also contribute a reusable library for reasoning about generic communicating state machines. Our mechanization consists of about 15k lines of Rocq code. We believe that our mechanization can provide the foundation for deductively proving the implementability of protocols beyond the reach of prior work, extracting certified implementations for finite protocols, and investigating implementability under alternative asynchronous communication models.
Cite as

Elaine Li and Thomas Wies. Certified Implementability of Global Multiparty Protocols. In 16th International Conference on Interactive Theorem Proving (ITP 2025). Leibniz International Proceedings in Informatics (LIPIcs), Volume 352, pp. 15:1-15:20, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2025)

Copy BibTex To Clipboard

@InProceedings{li_et_al:LIPIcs.ITP.2025.15,
  author =	{Li, Elaine and Wies, Thomas},
  title =	{{Certified Implementability of Global Multiparty Protocols}},
  booktitle =	{16th International Conference on Interactive Theorem Proving (ITP 2025)},
  pages =	{15:1--15:20},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-396-6},
  ISSN =	{1868-8969},
  year =	{2025},
  volume =	{352},
  editor =	{Forster, Yannick and Keller, Chantal},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ITP.2025.15},
  URN =		{urn:nbn:de:0030-drops-246139},
  doi =		{10.4230/LIPIcs.ITP.2025.15},
  annote =	{Keywords: Asynchronous protocols, communicating state machines, labeled transition systems, infinite semantics, realizability, multiparty session types, choreographies, deadlock freedom}
}
Document
DOI: 10.4230/LIPIcs.ECOOP.2025.31
Multiparty Asynchronous Session Types: A Mechanised Proof of Subject Reduction

Authors: Dawit Tirore, Jesper Bengtson, and Marco Carbone

Published in: LIPIcs, Volume 333, 39th European Conference on Object-Oriented Programming (ECOOP 2025)

Abstract
Session types offer a type-based approach to describing the message exchange protocols between participants in communication-based systems. Initially, they were introduced in a binary setting, specifying communication patterns between two components. With the advent of multiparty session types (MPST), the typing discipline was extended to arbitrarily many components. In MPST, communication patterns are given in terms of global types, an Alice-Bob notation that gives a global view of how components interact. A central theorem of MPST is subject reduction: a well-typed system remains well-typed after reduction. The literature contains some formulations of MPST with proofs of subject reduction that have later been shown to be incorrect. In this paper, we show that the subject reduction proof of the original formulation of MPST by Honda et al. contains some flaws. Additionally, we provide a restriction to the theory and show that, for this fragment, subject reduction does indeed hold. Finally, we use subject reduction to show that well-typed processes never go wrong. All of our proofs are mechanised using the Coq proof assistant.
Cite as

Dawit Tirore, Jesper Bengtson, and Marco Carbone. Multiparty Asynchronous Session Types: A Mechanised Proof of Subject Reduction. In 39th European Conference on Object-Oriented Programming (ECOOP 2025). Leibniz International Proceedings in Informatics (LIPIcs), Volume 333, pp. 31:1-31:30, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2025)

Copy BibTex To Clipboard

@InProceedings{tirore_et_al:LIPIcs.ECOOP.2025.31,
  author =	{Tirore, Dawit and Bengtson, Jesper and Carbone, Marco},
  title =	{{Multiparty Asynchronous Session Types: A Mechanised Proof of Subject Reduction}},
  booktitle =	{39th European Conference on Object-Oriented Programming (ECOOP 2025)},
  pages =	{31:1--31:30},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-373-7},
  ISSN =	{1868-8969},
  year =	{2025},
  volume =	{333},
  editor =	{Aldrich, Jonathan and Silva, Alexandra},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ECOOP.2025.31},
  URN =		{urn:nbn:de:0030-drops-233238},
  doi =		{10.4230/LIPIcs.ECOOP.2025.31},
  annote =	{Keywords: Session types, Multiparty, Mechanisation, Coq}
}
Document
Artifact
DOI: 10.4230/DARTS.11.2.3
Multiparty Asynchronous Session Types: A Mechanised Proof of Subject Reduction (Artifact)

Authors: Dawit Tirore, Jesper Bengtson, and Marco Carbone

Published in: DARTS, Volume 11, Issue 2, Special Issue of the 39th European Conference on Object-Oriented Programming (ECOOP 2025)

Abstract
Session types offer a type-based approach to describing the message exchange protocols between participants in communication-based systems. Initially, they were introduced in a binary setting, specifying communication patterns between two components. With the advent of multiparty session types (MPST), the typing discipline was extended to arbitrarily many components. In MPST, communication patterns are given in terms of global types, an Alice-Bob notation that gives a global view of how components interact. A central theorem of MPST is subject reduction: a well-typed system remains well-typed after reduction. The literature contains some formulations of MPST with proofs of subject reduction that have later been shown to be incorrect. In this paper, we show that the subject reduction proof of the original formulation of MPST by Honda et al. contains some flaws. Additionally, we provide a restriction to the theory and show that, for this fragment, subject reduction does indeed hold. Finally, we use subject reduction to show that well-typed processes never go wrong. All of our proofs are mechanised using the Coq proof assistant. This artifact accompanies our paper [Dawit Tirore et al., 2025]. It contains the Coq mechanisation of the theory described therein.
Cite as

Dawit Tirore, Jesper Bengtson, and Marco Carbone. Multiparty Asynchronous Session Types: A Mechanised Proof of Subject Reduction (Artifact). In Special Issue of the 39th European Conference on Object-Oriented Programming (ECOOP 2025). Dagstuhl Artifacts Series (DARTS), Volume 11, Issue 2, pp. 3:1-3:5, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2025)

Copy BibTex To Clipboard

@Article{tirore_et_al:DARTS.11.2.3,
  author =	{Tirore, Dawit and Bengtson, Jesper and Carbone, Marco},
  title =	{{Multiparty Asynchronous Session Types: A Mechanised Proof of Subject Reduction (Artifact)}},
  pages =	{3:1--3:5},
  journal =	{Dagstuhl Artifacts Series},
  ISSN =	{2509-8195},
  year =	{2025},
  volume =	{11},
  number =	{2},
  editor =	{Tirore, Dawit and Bengtson, Jesper and Carbone, Marco},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/DARTS.11.2.3},
  URN =		{urn:nbn:de:0030-drops-233467},
  doi =		{10.4230/DARTS.11.2.3},
  annote =	{Keywords: Session types, Multiparty, Mechanisation, Coq}
}
Document
DOI: 10.4230/LIPIcs.ITP.2024.13
Completeness of Asynchronous Session Tree Subtyping in Coq

Authors: Burak Ekici and Nobuko Yoshida

Published in: LIPIcs, Volume 309, 15th International Conference on Interactive Theorem Proving (ITP 2024)

Abstract
Multiparty session types (MPST) serve as a foundational framework for formally specifying and verifying message passing protocols. Asynchronous subtyping in MPST allows for typing optimised programs preserving type safety and deadlock freedom under asynchronous interactions where the message order is preserved and sending is non-blocking. The optimisation is obtained by message reordering, which allows for sending messages earlier or receiving them later. Sound subtyping algorithms have been extensively studied and implemented as part of various programming languages and tools including C, Rust and C-MPI. However, formalising all such permutations under sequencing, selection, branching and recursion in session types is an intricate task. Additionally, checking asynchronous subtyping has been proven to be undecidable. This paper introduces the first formalisation of asynchronous subtyping in MPST within the Coq proof assistant. We first decompose session types into session trees that do not involve branching and selection, and then establish a coinductive refinement relation over them to govern subtyping. To showcase our formalisation, we prove example subtyping schemas that appear in the literature, all of which cannot be verified, at the same time, by any of the existing decidable sound algorithms. Additionally, we take the (inductive) negation of the refinement relation from a prior work by Ghilezan et al. [Ghilezan et al., 2023] and re-implement it, significantly reducing the number of rules (from eighteen to eight). We establish the completeness of subtyping with respect to its negation in Coq, addressing the issues concerning the negation rules outlined in the previous work [Ghilezan et al., 2023]. In the formalisation, we use the greatest fixed point of the least fixed point technique, facilitated by the paco library, to define coinductive predicates. We employ parametrised coinduction to prove their properties. The formalisation consists of roughly 10K lines of Coq code, accessible at: https://github.com/ekiciburak/sessionTreeST/tree/itp2024.
Cite as

Burak Ekici and Nobuko Yoshida. Completeness of Asynchronous Session Tree Subtyping in Coq. In 15th International Conference on Interactive Theorem Proving (ITP 2024). Leibniz International Proceedings in Informatics (LIPIcs), Volume 309, pp. 13:1-13:20, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2024)

Copy BibTex To Clipboard

@InProceedings{ekici_et_al:LIPIcs.ITP.2024.13,
  author =	{Ekici, Burak and Yoshida, Nobuko},
  title =	{{Completeness of Asynchronous Session Tree Subtyping in Coq}},
  booktitle =	{15th International Conference on Interactive Theorem Proving (ITP 2024)},
  pages =	{13:1--13:20},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-337-9},
  ISSN =	{1868-8969},
  year =	{2024},
  volume =	{309},
  editor =	{Bertot, Yves and Kutsia, Temur and Norrish, Michael},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ITP.2024.13},
  URN =		{urn:nbn:de:0030-drops-207418},
  doi =		{10.4230/LIPIcs.ITP.2024.13},
  annote =	{Keywords: asynchronous multiparty session types, session trees, subtyping, Coq}
}
Document
DOI: 10.4230/LIPIcs.ITP.2023.28
A Sound and Complete Projection for Global Types

Authors: Dawit Tirore, Jesper Bengtson, and Marco Carbone

Published in: LIPIcs, Volume 268, 14th International Conference on Interactive Theorem Proving (ITP 2023)

Abstract
Multiparty session types is a typing discipline used to write specifications, known as global types, for branching and recursive message-passing systems. A necessary operation on global types is projection to abstractions of local behaviour, called local types. Typically, this is a computable partial function that given a global type and a role erases all details irrelevant to this role. Computable projection functions in the literature are either unsound or too restrictive when dealing with recursion and branching. Recent work has taken a more general approach to projection defining it as a coinductive, but not computable, relation. Our work defines a new computable projection function that is sound and complete with respect to its coinductive counterpart and, hence, equally expressive. All results have been mechanised in the Coq proof assistant.
Cite as

Dawit Tirore, Jesper Bengtson, and Marco Carbone. A Sound and Complete Projection for Global Types. In 14th International Conference on Interactive Theorem Proving (ITP 2023). Leibniz International Proceedings in Informatics (LIPIcs), Volume 268, pp. 28:1-28:19, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2023)

Copy BibTex To Clipboard

@InProceedings{tirore_et_al:LIPIcs.ITP.2023.28,
  author =	{Tirore, Dawit and Bengtson, Jesper and Carbone, Marco},
  title =	{{A Sound and Complete Projection for Global Types}},
  booktitle =	{14th International Conference on Interactive Theorem Proving (ITP 2023)},
  pages =	{28:1--28:19},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-284-6},
  ISSN =	{1868-8969},
  year =	{2023},
  volume =	{268},
  editor =	{Naumowicz, Adam and Thiemann, Ren\'{e}},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ITP.2023.28},
  URN =		{urn:nbn:de:0030-drops-184039},
  doi =		{10.4230/LIPIcs.ITP.2023.28},
  annote =	{Keywords: Session types, Mechanisation, Projection, Coq}
}
  • Refine by Type
  • 7 Document/PDF
  • 3 Document/HTML

  • Refine by Publication Year
  • 5 2025
  • 1 2024
  • 1 2023

  • Refine by Author
  • 3 Bengtson, Jesper
  • 3 Carbone, Marco
  • 3 Tirore, Dawit
  • 1 Accattoli, Beniamino
  • 1 Ekici, Burak
  • Show More...

  • Refine by Series/Journal
  • 6 LIPIcs
  • 1 DARTS

  • Refine by Classification
  • 2 Theory of computation → Logic and verification
  • 2 Theory of computation → Process calculi
  • 2 Theory of computation → Program specifications
  • 2 Theory of computation → Type structures
  • 2 Theory of computation → Type theory
  • Show More...

  • Refine by Keyword
  • 4 Coq
  • 3 Mechanisation
  • 3 Session types
  • 2 Multiparty
  • 1 Asynchronous protocols
  • Show More...

Any Issues?
X

Feedback on the Current Page

CAPTCHA

Thanks for your feedback!

Feedback submitted to Dagstuhl Publishing

Could not send message

Please try again later or send an E-mail
© 2023-2026 Schloss Dagstuhl – LZI GmbH Schloss Dagstuhl – LZI GmbH About DROPS Imprint Privacy Contact