You could have invented type classes!
We look at how the authors of SICP almost invented type classes and some tricks for using them in Haskell. We also find out why the Apollo capsule position in lunar orbit was not known to greater precision than 10 metres.
You have arrived at the mid-week hump. Have a $container of $beverage and enjoy some reading before you speed along with the rest of your life.
New articles
Data-directed programming in Haskell (SICP 2.4.3)
The authors of the wizard book move on from tagging types to inventing their own system for generics that ends up being very close to type classes. Let's see how it translates, and maybe learn something along the way!
Full article (8–20 minute read): Data-directed programming in Haskell (SICP 2.4.3)
Flashcard of the week
From the book Digital Apollo:
How accurately could ground tracking determine the position of the Apollo capsule in lunar orbit?
The interesting part of this is not the answer, which is
Around 10 metres
The interesting part is that the primary limitation to improving this number was that they didn't know the position of the antennae on Earth with greater accuracy!
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