Design Patterns vs. Anti-pattern in APL

schedule Nov 18th 02:00 PM - 02:45 PM place Studio 4 people 14 Attending

APL is a notorious language with a reputation for being "write only" and difficult to learn. Yet, many people consider APL to be their single most productive, advantageous tool that they hope never to give up. In particular, it is generally observed that many computer scientists have a poor opinion of the usability of APL, while many data scientists and domain experts find the language to be exceptionally usable.

This session focuses on the experienced programmer's struggle to gain real facility with APL beyond the basic, trivial understanding of its semantics and syntax (which can be taught in a few hours). We will observe this struggle through a "human-centered" experience analysis identifying a set of Pattern/Anti-pattern tensions that are at the heart of the intermediate APL learning "wall." By examining the experience of thinking and working with APL code versus regular code, we can identify principles of APL coding practice that directly oppose the widely taught and embraced best practices of the broader programming community. We'll see not only what these principles are, but also why they survive in APL and how they contribute to the positive development cycle of an experienced APL programmer, instead of the negative impact such practices usually have when writing in other languages.

Understanding these practices will provide a focus point for the discussion of programming experience design and the use of concise array language, as well as provide a structure for becoming better able to write, read, and think in APL expert.

 
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Outline/structure of the Session

  • Why don't computer scientists like APL?
  • So you want to learn APL?
  • The Birth of APL: Design Principles
  • The Design Patterns Dichotomy
  • APL Programming Styles
  • The Myth of Readability
  • Conclusion

Learning Outcome

  • Understand the issues surrounding learning real competency with APL.
  • Have a concrete plan for improving your ability to work with Array Programming concepts.
  • Better understand the tensions between APL programming styles and traditional methods.
  • Be better able to read and understand APL programs or programs written under similar design principles.

Target Audience

Anyone interested in programming best practices, language design, productivity, and the programming experience.

Prerequisite

It will be helpful for attendees to be experienced programmers who are familiar with existing industry best practices. It may also be helpful for anyone interested in gaining a deeper insight to these issues to first experiment with APL through YouTube videos (like Conway's Game of Life in APL) and through TryAPL.org before attending.

These are just suggestions, however, and are not necessary to gain something from the talk.

schedule Submitted 4 months ago

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comment Comment on this Proposal
  • Dhaval Dalal
    By Dhaval Dalal  ~  4 months ago
    reply Reply

    Hi Aaron,

         Thank-you for the proposal.  I'm really intrigued with this part of the description -  "we can identify principles of APL coding practice that directly oppose the widely taught and embraced best practices of the broader programming community."  which principles are you referring to?  If I remember Morten forwarding to me the bullets on 

    1. Macro vs. Micro
    2. Transparency vs. Abstraction
    3. Idioms vs. Libraries
    4. Data vs. Control Flow
    5. Structure vs. Names
    6. Concision vs. Verbosity
    7. Implicit vs. Explicit
    8. Syntax vs. Semantics

    Are these the ones?

    thanks,

    Dhaval.

    • Aaron W Hsu
      By Aaron W Hsu  ~  4 months ago
      reply Reply

      Yes, those 8 tensions are what I’m talking about. These tensions flow from the design principles Iverson describes in his Turing Award lecture, and how those principles were implemented in APL.

       

      • Dhaval Dalal
        By Dhaval Dalal  ~  4 months ago
        reply Reply

        I look forward to your session :)


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