docs(tvix/compiler): add a note on use of unwrap/expect for rnix

Change-Id: I62ca28285685b69d1883afcf18c6068fc2defb5d
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6149
Tested-by: BuildkiteCI
Reviewed-by: grfn <grfn@gws.fyi>
Reviewed-by: sterni <sternenseemann@systemli.org>
This commit is contained in:
Vincent Ambo 2022-08-11 14:07:37 +03:00 committed by tazjin
parent d9d94eb27f
commit f3f8262637

View file

@ -1,5 +1,17 @@
//! This module implements a compiler for compiling the rnix AST
//! representation to Tvix bytecode.
//!
//! A note on `unwrap()`: This module contains a lot of calls to
//! `unwrap()` or `expect(...)` on data structures returned by `rnix`.
//! The reason for this is that rnix uses the same data structures to
//! represent broken and correct ASTs, so all typed AST variants have
//! the ability to represent an incorrect node.
//!
//! However, at the time that the AST is passed to the compiler we
//! have verified that `rnix` considers the code to be correct, so all
//! variants are filed. In cases where the invariant is guaranteed by
//! the code in this module, `debug_assert!` has been used to catch
//! mistakes early during development.
use crate::chunk::Chunk;
use crate::errors::EvalResult;