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  • Jun 26, 2014 · 8:00 PM
  • Binary Kitchen e.V.

Lenses are an abstraction that allows you to easily access and modify parts of a potentially large data structure. The typical motivating example are lenses for fields of records. However, lenses can be composed, allowing for quick access deep into a nested structure, and also generalized in other ways, making them potentially a beautiful solution for a whole lot of programming problems.

I'm going to give a short introduction to classic lenses and their laws. Depending on what everyone is interested in, I'll then go on to look a bit at their implementation (there are several ways to represent a lens internally, some very straight-forward, others quite clever) and various forms of generalizations (such as lifting lenses into monads, or potentially traversals and prisms).

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  • Dan Ș.

    Could you please share a link to the slides? Thanks.

    June 27, 2014

    • Andres L.

      I'm sorry, I did not use any slides for this talk.

      June 30, 2014

  • Andres L.

    Ok, I've picked a date. Sorry Gabor. There wasn't a single date where everyone could make it, so I just went by number of yes/no votes.

    June 11, 2014

    • Gabor G.

      That's totally okay, I have seen the SPJ video on lens already, and I believe I understand it.

      June 12, 2014

  • Andres L.

    Please participate in the Doodle poll if you haven't done so yet:

    June 2, 2014

  • Andres L.

    Here's a Doodle poll for finding a good day:

    May 28, 2014

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