The Unreasonable Effectiveness of Dynamic Typing

A session at JavaZone 2013

Wednesday 11th September, 2013

1:00pm to 2:00pm (CET)

Explore the disconnect between the dire outcomes for dynamic language programs predicted by advocates of static typing, versus the near absence of type errors in real world systems built in Python, Ruby and Clojure and the many successful systems built in dynamic languages.

Some programming language theorists would have us believe that the one true path to working systems lies in powerful and expressive type systems which allow us to encode rich constraints into programs at the time they are created. If these academic computer scientists would get out more, they would soon discover an increasing incidence of software developed in languages such a Python, Ruby and Clojure which use dynamic, albeit strong, type systems. They would probably be surprised to find that much of this software—in spite of their well-founded type-theoretic hubris—actually works, and is indeed reliable out of all proportion to their expectations.

This talk—given by an experienced polyglot programmer who once implemented Hindley Milner static type inference for “fun”, but who now builds large and successful systems in Python—explores the disconnect between the dire outcomes predicted by advocates of static typing versus the near absence of type errors in real world systems built with dynamic languages: Does diligent unit testing more than make up for the lack of static typing? Does the nature of the type system have only a low-order effect on reliability compared to the functional or imperative programming paradigm in use? How often is the dynamism of the type system used anyway? How much type information can JITs exploit at runtime? Does the unwarranted success of dynamically typed languages get up the nose of people who write Haskell? For the answers to these important questions, and more, don’t miss this session.

About the speaker

This person is speaking at this event.
Robert Smallshire

Founder of Sixty North, an application, consulting and training business. Open source hacker and hobby technologist by night. Living and working in Oslo.

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JavaZone 2013

Norway Norway, Oslo

11th12th September 2013

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Time 1:00pm2:00pm CET

Date Wed 11th September 2013

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