Publications related to Substructural type system

Formal Foundations of Capture Tracking

Type systems are a device for verifying properties of programs without running them. Many programming languages used in the industry have always had a type system, while others were initially created without a type system and later adopted one, when the ad ...

EPFL2024

Degrees of Separation: A Flexible Type System for Safe Concurrency

Martin Odersky, Yichen Xu, Aleksander Slawomir Boruch-Gruszecki

Data races have long been a notorious problem in concurrent programming. They are subtle to detect, and lead to non-deterministic behaviours. There has been a lot of interest in type systems that statically guarantee data race freedom. Significant progress ...

2024

Capturing Types

Martin Odersky, Aleksander Slawomir Boruch-Gruszecki, Ondrej Lhoták

Type systems usually characterize the shape of values but not their free variables. However, many desirable safety properties could be guaranteed if one knew the free variables captured by values. We describe CC

Assoc Computing Machinery2023

The Simple Essence of Algebraic Subtyping: Principal Type Inference with Subtyping Made Easy

Lionel Emile Vincent Parreaux

MLsub extends traditional Hindley-Milner type inference with subtyping while preserving compact principal types, an exciting new development. However, its specification in terms of biunification is difficult to understand, relying on the new concepts of bi ...

2020

Safe Initialization of Objects

Martin Odersky, Fengyun Liu, Paolo Giosuè Giarrusso, Ondrej Lhoták

Every newly created object goes through several initialization states: starting from a state where all fields are uninitialized until all of them are assigned. Any operation on the object during its initialization process, which usually happens in the cons ...

2020

A Type-and-Effect System for Object Initialization

Martin Odersky, Fengyun Liu, Paolo Giosuè Giarrusso, Ondrej Lhoták

Every newly created object goes through several initialization states: starting from a state where all fields are uninitialized until all of them are assigned. Any operation on the object during its initialization process, which usually happens in the cons ...

ASSOC COMPUTING MACHINERY2020

Type-Safe Metaprogramming and Compilation Techniques For Designing Efficient Systems in High-Level Languages

Lionel Emile Vincent Parreaux

Software engineering practices have been steadily moving towards higher-level programming languages and away from lower-level ones. High-level languages tend to greatly improve safety, productivity, and code maintainability because they handle various impl ...

EPFL2020

Safe initialization of objects

Fengyun Liu

The inception of object-oriented programming introduces a category of bugs related to object construction: initialization errors. Every newly created object goes through several initialization states: starting from a state where all fields are uninitialize ...

EPFL2020

On subadditivity of Kodaira dimension in positive characteristic over a general type base

Zsolt Patakfalvi

We show that for a surjective, separable morphism f of smooth projective varieties over a field of positive characteristic such that f(*) OX congruent to O-Y subadditivity of Kodaira dimension holds, provided the base is of general type and the Hasse-Witt ...

2018

Monotonicity Types for Distributed Dataflow

Heather Christine Klug

The Lasp programming language provides combinator functions such as Union and Intersection for combining set CRDTs. When designing a CRDT combinator, care must be taken to ensure that the combinator is monotone separately in each of its arguments, so that ...

2017

Monotonicity Types

Heather Christine Klug

In the face of the increasing trend in application development to interact with more and more remote services, and cognizant of the fact that issues arising from data consistency and task coordination are core challenges in distributed programming, the sys ...

2017

Functional BIP: Embedding connectors in functional programming languages

Romain Edelmann, Joseph Sifakis, Simon Bliudze

This paper presents a theoretical foundation for functional language implementations of Behaviour–Interaction–Priority (BIP). We introduce a set of connector combinators describing synchronisation, data transfer, priorities and dynamicity in a principled w ...

Elsevier Science Inc2017

Type Soundness Proofs with Definitional Interpreters

Tiark Rompf, Nada Amin

While type soundness proofs are taught in every graduate PL class, the gap between realistic languages and what is accessible to formal proofs is large. In the case of Scala, it has been shown that its formal model, the Dependent Object Types (DOT) calculu ...

Assoc Computing Machinery2017

Predictive models for assessing the passive solar and daylight potential of neighborhood designs: A comparative proof-of-concept study

Marilyne Andersen, Emmanuel Rey, Émilie Nault

Despite recent developments, neighborhood-scale performance assessment at the early-design phase is seldom carried out in practice, notably due to high computational complexity, time requirement, and perceived need for expert knowledge, ultimately limiting ...

2017

Higher-Order Subtyping with Type Intervals

Sandro Stucki

Modern, statically typed programming languages provide various abstraction facilities at both the term- and type-level. Common abstraction mechanisms for types include parametric polymorphism -- a hallmark of functional languages -- and subtyping -- which ...

EPFL2017

Squid: Type-Safe, Hygienic, and Reusable Quasiquotes

Christoph Koch, Amir Shaikhha, Lionel Emile Vincent Parreaux

Quasiquotes have been shown to greatly simplify the task of metaprogramming. This is in part because they hide the data structures of the intermediate representation (IR), instead allowing metaprogrammers to use the concrete syntax of the language they man ...

ACM2017

Adaptive WENO methods based on radial basis functions reconstruction

Jan Sickmann Hesthaven, Caterina Bigoni

We explore the use of radial basis functions (RBF) in the weighted essentially non-oscillatory (WENO) reconstruction process used to solve hyperbolic conservation laws, resulting in a numerical method of arbitrarily high order to solve problems with discon ...

Springer Verlag2017

Java and Scala's Type Systems are Unsound The Existential Crisis of Null Pointers

Nada Amin

We present short programs that demonstrate the unsoundness of Java and Scala's current type systems. In particular, these programs provide parametrically polymorphic functions that can turn any type into any type without (down) casting. Fortunately, parame ...

Assoc Computing Machinery2016

SMT-Based Checking of Predicate-Qualified Types for Scala

Viktor Kuncak, Georg Stefan Schmid

We present qualified types for Scala, a form of refinement types adapted to the Scala language. Qualified types allow users to refine base types and classes using predicate expressions. We implemented a type checker for qualified types that is embedded in ...

Assoc Computing Machinery2016

Automating Ad hoc Data Representation Transformations

Martin Odersky, Vlad Ureche

To maximize run-time performance, programmers often specialize their code by hand, replacing library collections and containers by custom objects in which data is restructured for efficient access. However, changing the data representation is a tedious and ...

Assoc Computing Machinery2015