I suppose I should clarify, I would consider a basic AST the sane choice when talking about creating toy compilers as a learning experience - as opposed to crea

I suppose I should clarify, I would consider a basic AST the sane choice when talking about creating toy compilers as a learning experience - as opposed to creating a compiler that just reads in text and spits out assembly without any real intermediate representation. Which, there are legitimate compilers that do that (And as you mentioned, older compilers tended to work this way as well), but for learning I don't really think you get nearly as much out of doing it that way. That said, if you want to do something more advanced or use or use something better then a basic AST, I agree go for it. But if you're actually writing the compiler for a project that isn't just a toy or as a learning experience, you're almost definitely better off just building a frontend on an existing platform like LLVM.