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π-calculus, Session Types research at Imperial College

Lightweight Session Programming in Scala
Alceste SCALAS , Nobuko YOSHIDA
30th European Conference on Object-Oriented Programming (ECOOP 2016) p. 21:1 - 21:28

Designing, developing and maintaining concurrent applications is an error-prone and time-consuming task; most difficulties arise because compilers are usually unable to check whether the inputs/outputs performed by a program at runtime will adhere to a given protocol specification.

To address this problem, we propose lightweight session programming in Scala: we leverage the native features of the Scala type system and standard library, to introduce (1) a representation of session types as Scala types, and (2) a library called lchannels with a convenient API for session-based programming, supporting local and distributed communication. We generalise the idea of Continuation-Passing Style Protocols (CPSPs), studying their formal relationship with session types. We illustrate how session programming can be carried over in Scala: how to formalise a communication protocol, and represent it using Scala classes and lchannels, letting the compiler help spotting protocol violations. We attest the practicality of our approach with a complex use case, and evaluate the performance of lchannels with a series of benchmarks.

@inproceedings{SY2016,
  author = {Alceste Scalas and Nobuko Yoshida},
  title = {{Lightweight Session Programming in Scala}},
  booktitle = {30th European Conference on Object-Oriented Programming},
  series = {LIPIcs},
  pages = {21:1--21:28},
  publisher = {Dagstuhl},
  year = 2016
}
@inproceedings{SY2016,
  author = {Alceste Scalas and Nobuko Yoshida},
  title = {{Lightweight Session Programming in Scala}},
  booktitle = {30th European Conference on Object-Oriented Programming},
  series = {LIPIcs},
  pages = {21:1--21:28},
  publisher = {Dagstuhl},
  doi = "10.4230/LIPIcs.ECOOP.2016.21",
  year = 2016
}