backslash_16

Hi Hacker News,

I'm working on a c compiler from scratch and am in a bit of a deadzone figuring out how I can test the generated AST and assembly output. I'm specifically having a hard time finding something that is viable for a one person project and which is also useful.

I did some research on Clang and saw they use a custom Filecheck library. This looks incredible for a production grade compiler but for mine I'm not sure if I want to put in all of the effort (especially because my host language F# doesn't have a Filecheck lib and I would have to re-create it).

Same with the AST - the best I can think of is creating the nodes in my host code language. This is verbose.

What have you done to test and check your compiler output, any good recommendations for me? I'm happy to research or read anything. Please keep in mind I'm going for a good effort to reward ratio.

I've never really worked with containers in my professional career and I'm learning about them now.

It's hard to tell from reading online if people are using them for their dev environments or if they're developing on their host (or native, whatever you want to call it) and using a container to package the application after its built.

What do you use containers for? Do you setup your dev environment in a container, and if you do, I've got tons of questions.

- Do you do it for every language? - Do you install your static analysis and other tools in the container? - Do you debuggers work (Visual Studio, gdb, pdb, whatever)

If you use a container for only your post-development workflow do you ever use separate containers for build and test vs the final packaged application?

Hey HN, I'm curious about what happens to engineers who have unvested stock grants at Twitter.

Do they get cash instead, do they immediately grant, or do they go poof and disappear?

I'm working through the excellent Crafting Interpreters book and learning Rust at the same time by writing the interpreter in the first part of the book in Rust. For anyone who hasn't read the book, you totally should!, you implement an interpreter for a made up dynamically typed language called Lox.

The scanner was relatively straightforward and now I'm having a hard time figuring out how I can implement a data structure to contain the AST for Lox. I'm pretty sure the core question is "How do I represent a tree of heterogeneous objects in Rust?"

In the book he uses polymorphism. There is a base class of Expression, with subclasses for each expression type.

At this point I think I'm holding Rust wrong and approaching the problem the wrong way. Potentially because I've used OOP for must of my life, with any functional-ish programming being pure functions, C#'s LINQ, and emulating concepts like free functions that act on data in C# or Java.

This is the specific part of the book where I'm having trouble. http://craftinginterpreters.com/representing-code.html#implementing-syntax-trees

I have the sense that I need to use a struct with an enum of expression type as the data field but I can't figure out to tie the data into it in a nice way. Is it as simple as having each variant of the enum contain the "complex" data structure that represents that expression kind?

Can someone poke or prod me in the right direction? I'm doing this for the sole purpose of learning so I don't necessarily want to be given the answer.