I realize this is something I should probably know but I've never been able to pin down a definition nor have I used a language with this feature -- could you maybe explain what a "content addressable language" is and why that is important? It seems like it's really important but I have no idea why. You explain it here[1] but it's somewhat brief. I realize it probably should be self-evident why it's important but it's not clicking for me.
It's somewhat like when Jack Skelington is trying to explain the meaning of Christmas to the residents of Halloween Town[2] and somehow it hasn't stuck yet.
To be clear, I am not Taylor and I did not come up with scrapscript! That website belongs to him and I'm just a random guy on the internet who emailed him and built an implementation.
The way I think about it is kind of like software versions. Say you want to do some kind of reproducible software. You can write that your software depends on jazzinator==3.0.0 but that's kind of unsatisfying because it relies either on tools or people to make sure that versions are immutable. It also relies on jazzinator to specify its own dependencies pretty strictly. So maybe you end up inventing the concept of a lockfile to partially solve that problem, but you still have the issue of relying on a third party to not change things up on you.
However, if you can address a library by a name that is computed from its code (a hash), things get interesting. You end up with this tree/DAG of dependencies where every dependency is immutable--you can't change the code without also changing the name. It's a Merkle DAG like Git. You do lose the ability to say things like "above version 2.5"... sort of.
If you also build a ref or tag system (similar to Git refs), you can kinda do normal style versioning on top of this content addressable world. But again, that relies on someone or something (maybe your hash-based store) to keep a map point-version names to hash names.
The other thing that's interesting with scrapscript in particular is since everything is addressable, you can use (sort of implicitly import/download) any value from any other program in a repository readable by you. But no scrapscript implementation fully does this yet, as far as I'm aware. For a fully working system, check out Unison.
Oh that is really fascinating, thank you. That has some really interesting implications for dependency management that I will have to think through. It sounds like that implies some really useful tree properties on dependency checking, like if the part of the program you are relying on matches a certain hash you don't need to check down the chain because you can be sure the rest of the nodes are as you expect.
