tvl-depot/tvix/eval
sterni 4d8f35353b fix(tvix/eval): declare let inherit (from) locals before compiling
The recent change that split declaration of let based locals and the
compilation of their values did not touch locals bound by inherit in
let. These were previously declared and compiled immediately before
starting to work on the other locals introduced in a let.

In the case of plain inherits, this behavior is kept in this change,
because there's nothing wrong with it: The value of a plain inherit will
always resolve to a higher scope, either statically or dynamically.

Since inherit (from) expression might refer to other locals bound in the
same let, we need to handle them in the same three steps as ordinary let
based locals:

1. We need to declare the (uninitialised) locals.

2. We need to compile the expression that obtains their value. For this,
   we create a new thunk, since the from expression may very well return
   a thunk which we need to force before selecting the value we are
   interested in.

3. Thunks need to be finalised.

For 1., we create an extra pass over the inherits that already declares
and initialises plain inherits and notes inherit (from) expressions in
the entries vector after declaring them. 2. only needs a bit of adapting
to create the thunks for selecting if appropriate, the rest of the
existing code can be reused.

Change-Id: Ie4ac1c0f9ffcbf7c07c452036aa8e577443af773
Reviewed-on: https://cl.tvl.fyi/c/depot/+/6490
Tested-by: BuildkiteCI
Reviewed-by: sterni <sternenseemann@systemli.org>
Reviewed-by: tazjin <tazjin@tvl.su>
2022-09-11 12:26:23 +00:00
..
benches test(tvix/eval): Add attr merge benchmarks 2022-09-03 06:56:02 +00:00
docs docs(tvix/eval): add some notes on recursive attribute sets 2022-09-11 12:26:23 +00:00
src fix(tvix/eval): declare let inherit (from) locals before compiling 2022-09-11 12:26:23 +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 feat(tvix/eval): implement DisassemblingObserver for compiler 2022-09-09 21:10:10 +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

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.