This essay says that inheritance is harmful and if possible you should “ban inheritance completely”. You see these arguments a lot, as well as things like “prefer composition to inheritance”. A lot of these arguments argue that in practice inheritance has problems. But they don’t preclude inheritance working in another context, maybe with a better language syntax. And it doesn’t explain why inheritance became so popular in the first place. I want to explore what’s fundamentally challenging about inheritance and why we all use it anyway.

  • NostraDavid
    link
    83 months ago

    just like followers of religion

    We say that shit, because we’ve touched code that’s deeply inherited, and it was a god-damn pain to work with, because changing a single line can mean you’ll need to update a fuckton more, which breaks tests all god-damn over, which means you may have to refactor 50% of the application in one go.

    Anyway, everything has its uses (even goto). It’s just there are typically better alternatives.

    “sum types” and “algebraic data types” are horrible names.

    Agreed, but they exist due to historic reasons, and now we’re stuck with them. Not much we can do there ¯\_(ツ)_/¯

    Pretty much the equivalent of “imaginary numbers”.

    Terrible name that just means “vertical number line” (with an added operation where you rotate the vector, instead of add or scale), or “y-axis for the number line”. It’s funny because “Real” numbers are about as real as “Imaginary” numbers. Both are virtual (not physically existing).

    str | int is a sum type

    It just means that the variable can either be a str or an int. You’ve seen | used as “bitwise or”, right? Think in that direction.

    PS: Stay away from Monads - they’ll give you an aneurysm. 😂

    • @[email protected]
      link
      fedilink
      English
      13 months ago

      In some langs like Python, | is also the “union” operator, to join sets and such, which I think is more directly related to types, since types are sets of possible values.