Reading Notes
=============

Brief thoughts and notes for reading the book `Practical Haskell: A Real World Guide to Programming`.

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Chapter 14
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The chapter first dives into `attribute grammer` by introducing various tools and focuses on a code generator named ``UUAGC``. I skimmed through this part since it's not really about Haskell but about a Haskell generator that has a syntax resembling the Haskell syntax. To be honest, it's a bit weird to see a code generator introduction in a language introduction book. I can write A Python generator equipped with a Python-like syntax, but I wouldn't recommend others to discuss it in a Python language introduction. A compiler or programming language design course would be more appropriate.

After the introduction of attribute grammer, the book goes through a generalized version of fold, also known as `catamorphisms` by mathematicians in category-theory. The term :math:`D`-`algebra` is also defined. It's a tuple of all the functions that are needed to perform a fold on a data structure. Lastly, unfold is another term for `anamorphism`. The core idea of generalized fold is replacing data constructors with a different function that evaluates to (more) concrete values.

Lastly, it briefly introduces `data type-generic programming`. As recognized by the author, the presentation is short and is only meant to give a taste on what it's. Other more in-depth material is needed for better understanding.