Add a method for accessing the constant pool by index about cafebabe

[staktrace]

I've been meaning to work on exposing the code data in a better way. The library could implement bytecode parsing and return opcodes with their associated data (including constant pool references) as first class data structures.

I'd be interested in hearing more about your use case for the library to design the API accordingly.

The API you suggested is slightly more complicated than it might first seem because some entries in the constant pool (long/double values) take up two indices and you'd have to account for that. Not hard, but it would be a linear iteration rather than constant time.

[accusitive]

Any update on this? Its the current blocker for one of my projects.

[staktrace]

@accusitive can you provide more details on your use case and what you're trying to do? It would help inform the API design.

[zigazeljko]

@accusitive I suggest using the noak crate.

@staktrace Check out the ConstantPool::get method in the linked crate for an idea for the API.

[staktrace]

@staktrace Check out the ConstantPool::get method in the linked crate for an idea for the API.

Coming up with an API isn't hard. That's not the point. The point is to understand the use cases so that the API can be properly designed. My expectation when writing this library was that in the majority of cases users wouldn't need to manually iterate through the constant pool. Instead, the library could provider higher-level abstractions that make the manual iteration unnecessary. If that's not the case then I'd like to understand why.

[accusitive]

Hey, sorry for not responding, I've been rewriting my program a few times to try to solve an unrelated problem.

My use case is a jvm bytecode to llvm compiler, for fun.
In this case I needed it to support calling something like System.out.println(), since basic functions themselves was working, but couldn't do much more than basic math, variables, and calling other functions (implemented in C or Java).

[staktrace]

Thanks. Yeah for bytecode manipulation In thinking of writing a strongly-typed structure that provides direct access to the resolved constant pool entries referenced by the bytecode. So you wouldn't need to iterate through the constant pool yourself, the code would provide all the associated constants directly.

At some point I'll get around to implementing that, but this is a back-burner project for me at the moment so I can't commit to timelines.

[accusitive]

Good to hear, for now im trying noak and its pretty nice. Although this project was a lot more elegant :)

[staktrace]

FYI I added some bytecode parsing stuff. It's on the main branch but I haven't published a new release yet.

[accusitive]

I've been trying it out, and its great, No complaints from me.

[accusitive]

The bytecode parsing stuff just helped me implement branching, which I'd been trying for 4 days. (see: I've been rewriting my program a few times to try to solve an unrelated problem.)
I can't thank you enough for this :)