Lwt: a cooperative thread library

ABSTRACT

We present a cooperative thread library for Objective Caml. The library is entirely written in Objective Caml and does not rely on any external C function. Programs involving threads are written in a monadic style. This makes it possible to write threaded code almost as regular ML code, even though it has a different semantics. Cooperative threads are especially well suited for concurrent network applications, where threads perform little computation and spend most of their time waiting for input or output, at which time other threads can run. This library has been successfully used in the Unison file synchronizer and the Ocsigen Web server.

REFERENCES

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INDEX TERMS

Primary Classification:
  D. Software
  D.1 PROGRAMMING TECHNIQUES
      D.1.1 Applicative (Functional) Programming

Additional Classification:
  D. Software
  D.1 PROGRAMMING TECHNIQUES
      D.1.3 Concurrent Programming
  D.3 PROGRAMMING LANGUAGES
      D.3.3 Language Constructs and Features
          Subjects: Concurrent programming structures

General Terms:
Design, Languages

Keywords:
concurrency, implementation, ml, monad, networking, objective caml, programming, thread