Let's Lens presents a series of exercises, in a similar format to the Data61 functional programming course material. The subject of the exercises is around the concept of lenses, initially proposed by Foster et al., to solve the view-update problem of relational databases.
The theories around lenses have been advanced significantly in recent years, resulting in a library, implemented in Haskell, called lens.
This workshop will take you through the basic definition of the lens data structure and its related structures such as traversals and prisms. Following this we implement some of the low-level lens library, then go on to discuss and solve a practical problem that uses all of these structures.
An attendee who completes this workshop should expect to confidently use the lens library, or other similar libraries, in their every day programming.
schedule Submitted 2 years ago
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