History

Vincent Ambo 377ba19d75 feat(tvix/eval): ensure all errors always carry a span Previously error spans were optional because the information about code spans was not available at runtime. Now that this information has been added, the error type will always carry a span. This change is very invasive all throughout the codebase. This is due to the fact that many functions that are called by the VM expected to return `EvalResult`, but this no longer works as the span information is not available to those functions - only to the VM itself. To work around this the majority of these functions have been changed to return `Result<T, ErrorKind>` instead and an accompanying macro in the VM constructs the "real" error. Note that this implementatino currently has a bug where errors occuring within thunks will yield the location at which the thunk was forced, not the location at which the error occured within the code. This will be fixed soon, but the commit is large enough as is. Change-Id: Ib1ecb81a4d09d464a95ea7ea9e589f3bd08d5202 Reviewed-on: https://cl.tvl.fyi/c/depot/+/6408 Reviewed-by: sterni <sternenseemann@systemli.org> Tested-by: BuildkiteCI		2022-09-08 07:59:15 +00:00
..
benches	test(tvix/eval): Add attr merge benchmarks	2022-09-03 06:56:02 +00:00
docs	docs(tvix/eval): start a document on known optimisation potential	2022-09-06 07:29:25 +00:00
src	feat(tvix/eval): ensure all errors always carry a span	2022-09-08 07:59:15 +00:00
.gitignore	feat(tvix/eval): check in generated project skeleton	2022-08-12 12:34:29 +00:00
.skip-subtree	feat(tvix/tests): check in Nix' language test suite	2022-08-24 21:25:41 +00:00
Cargo.lock	chore(tvix/eval): bump all dependencies	2022-09-07 19:08:56 +00:00
Cargo.toml	chore(tvix/eval): bump all dependencies	2022-09-07 19:08:56 +00:00
default.nix	fix(tvix/eval): don't rebuild drv upon changes in cargo target dir	2022-09-04 21:02:50 +00:00
README.md	docs(tvix/eval): add a note on how to run Nix tests	2022-09-03 00:47:58 +00:00

README.md

Tvix Evaluator

This project implements an interpreter for the Nix programming language.

The interpreter aims to be compatible with nixpkgs, on the foundation of Nix 2.3.

Work on this project is extremely in-progress, and the state of the project in the public repository may not necessarily reflect the state of the private codebase, as we are slowly working on publishing it.

We expect this to have caught up in a handful of weeks (as of 2022-08-12).

Please contact TVL with any questions you might have.

Nix test suite

C++ Nix implements a language test suite in the form of Nix source code files, and their expected output. The coverage of this test suite is not complete, but we intend to be compatible with it.

We have ported the test suite to Tvix, but do not run it by default as we are not yet compatible with it.

You can run the test suite by enabling the nix_tests feature in Cargo:

cargo test --features nix_tests

rnix-parser

Tvix is written in memory of jD91mZM2, the author of rnix-parser who sadly passed away.

Tvix makes heavy use of rnix-parser in its bytecode compiler. The parser is now maintained by Nix community members.