This removes the runtime dependency on a borrow into the program
source code.
It's not yet ideal because there are a lot of tokens where we really
don't care about the lexeme, but this is what the book does and I
am not going to change that.
Change-Id: I888e18f98597766d6f725cbf9241e8eb2bd839e2
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2394
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
In order to store a function in the interpreter's representation of a
callable, the lifetimes used throughout rlox need to be threaded
through properly.
This is currently not optimal, for two reasons:
* following the design of the book's scanner, the source code slice
needs to still be available at runtime. Rust makes this explicit,
but it seems unnecessary.
* the interpreter's lifetime is now bounded to be smaller than the
source's, which means that the REPL no longer persists state between
evaluations
Both of these can be fixed eventually by diverging the scanner from
the book slightly, but right now that's not my priority.
Change-Id: Id0bf694541ff59795cfdea3c64a965384a49bfe2
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2391
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
... mostly some AST boilerplate and a first top-level rule, plus
boilerplate similar to that set up in the Scanner.
Change-Id: I605d1de23c47a3b3702ab4f62cd3371bc3988c7d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2194
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
... still not that interesting, but at this point slightly divergent
from the book:
The book embraces mutability for interpreter state, initially for
tracking whether an error condition has occured.
I avoid this by instead defining an error type and collecting the
error values, to be handled later on.
Notes: So far nothing special, but this is just the beginning of the
book. I like the style it is written in and it has pointed to some
interesting resources, such as a 1965 paper titled "The Next 700
Languages".
Change-Id: I030b38438fec9eb55372bf547af225138908230a
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2144
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
... as well as a Nix derivation, because why not.
Change-Id: Iaf2591ab72676fe0732c3f807b3aa0cff13fb4ef
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2143
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
This is going to be the first of two interpreters from "Crafting
Interpreters".
Change-Id: I354ddd2357444648d0245f35d92176dd176525d8
Reviewed-on: https://cl.tvl.fyi/c/depot/+/2142
Reviewed-by: tazjin <mail@tazj.in>
Tested-by: BuildkiteCI
