025c67bf4d
Warning: This is probably the biggest refactor in tvix-eval history, so far. This replaces all instances of trampolines and recursion during evaluation of the VM loop with generators. A generator is an asynchronous function that can be suspended to yield a message (in our case, vm::generators::GeneratorRequest) and receive a response (vm::generators::GeneratorResponsee). The `genawaiter` crate provides an interpreter for generators that can drive their execution and lets us move control flow between the VM and suspended generators. To do this, massive changes have occured basically everywhere in the code. On a high-level: 1. The VM is now organised around a frame stack. A frame is either a call frame (execution of Tvix bytecode) or a generator frame (a running or suspended generator). The VM has an outer loop that pops a frame off the frame stack, and then enters an inner loop either driving the execution of the bytecode or the execution of a generator. Both types of frames have several branches that can result in the frame re-enqueuing itself, and enqueuing some other work (in the form of a different frame) on top of itself. The VM will eventually resume the frame when everything "above" it has been suspended. In this way, the VM's new frame stack takes over much of the work that was previously achieved by recursion. 2. All methods previously taking a VM have been refactored into async functions that instead emit/receive generator messages for communication with the VM. Notably, this includes *all* builtins. This has had some other effects: - Some test have been removed or commented out, either because they tested code that was mostly already dead (nix_eq) or because they now require generator scaffolding which we do not have in place for tests (yet). - Because generator functions are technically async (though no async IO is involved), we lose the ability to use much of the Rust standard library e.g. in builtins. This has led to many algorithms being unrolled into iterative versions instead of iterator combinations, and things like sorting had to be implemented from scratch. - Many call sites that previously saw a `Result<..., ErrorKind>` bubble up now only see the result value, as the error handling is encapsulated within the generator loop. This reduces number of places inside of builtin implementations where error context can be attached to calls that can fail. Currently what we gain in this tradeoff is significantly more detailed span information (which we still need to bubble up, this commit does not change the error display). We'll need to do some analysis later of how useful the errors turn out to be and potentially introduce some methods for attaching context to a generator frame again. This change is very difficult to do in stages, as it is very much an "all or nothing" change that affects huge parts of the codebase. I've tried to isolate changes that can be isolated into the parent CLs of this one, but this change is still quite difficult to wrap one's mind and I'm available to discuss it and explain things to any reviewer. Fixes: b/238, b/237, b/251 and potentially others. Change-Id: I39244163ff5bbecd169fe7b274df19262b515699 Reviewed-on: https://cl.tvl.fyi/c/depot/+/8104 Reviewed-by: raitobezarius <tvl@lahfa.xyz> Reviewed-by: Adam Joseph <adam@westernsemico.com> Tested-by: BuildkiteCI |
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| .gcroots | ||
| .nixery | ||
| corp | ||
| docs | ||
| fun | ||
| lisp | ||
| net | ||
| nix | ||
| ops | ||
| third_party | ||
| tools | ||
| tvix | ||
| users | ||
| views | ||
| web | ||
| .envrc | ||
| .git-blame-ignore-revs | ||
| .gitignore | ||
| .hgignore | ||
| .mailmap | ||
| .rgignore | ||
| buf.gen.yaml | ||
| buf.yaml | ||
| default.nix | ||
| LICENSE | ||
| OWNERS | ||
| README.md | ||
| RULES | ||
| rustfmt.toml | ||
depot
This repository is the monorepo for the community around The Virus Lounge, containing our personal tools and infrastructure. Everything in here is built using Nix.
A large portion of the software here is very self-referential, meaning that it exists to sustain the operation of the repository. This is the case because we partially see this as an experiment in tooling for monorepos.
Highlights
Services
-
Source code is available primarily through Sourcegraph on cs.tvl.fyi, where it is searchable and even semantically indexed. A lower-tech view of the repository is also available via cgit-pink on code.tvl.fyi.
The repository can be cloned using
gitfromhttps://cl.tvl.fyi/depot. -
All code in the depot, with the exception of code that is checked in to individual
//usersfolders, needs to be reviewed. We use Gerrit on cl.tvl.fyi for this. -
Issues are tracked via our own issue tracker on b.tvl.fyi. Its source code lives at
//web/panettone/. -
Smaller todo-list entries which do not warrant a separate issue are listed at todo.tvl.fyi.
-
We use Buildkite for CI. Recent builds are listed on tvl.fyi/builds and pipelines are configured dynamically via
//ops/pipelines. -
A search service that makes TVL services available via textual shortcuts is available: atward
All services that we host are deployed on NixOS machines that we manage. Their
configuration is tracked in //ops/{modules,machines}.
Nix
//nix/readTreecontains the Nix code which automatically registers projects in our Nix attribute hierarchy based on their in-tree location//tools/nixerycontains the source code of Nixery, a container registry that can build images ad-hoc from Nix packages//nix/yantscontains Yet Another Nix Type System, which we use for a variety of things throughout the repository//nix/buildGoimplements a Nix library that can build Go software in the style of Bazel'srules_go. Go programs in this repository are built using this library.//nix/buildLispimplements a Nix library that can build Common Lisp software. Currently only SBCL is supported. Lisp programs in this repository are built using this library.//web/blogand//web/atom-feed: A Nix-based static site generator which generates the web page and Atom feed for tazj.in (//users/tazjin/homepage) and tvl.fyi (//web/tvl)//web/bubblegumcontains a CGI-based web framework written in Nix.//nix/nint: A shebang-compatible interpreter wrapper for Nix.//tvixcontains initial work towards a modular architecture for Nix.
We have a variety of other tools and libraries in the //nix folder which may
be of interest.
Packages / Libraries
//net/alcoholic_jwtcontains an easy-to-use JWT-validation library for Rust//net/crimpcontains a high-level HTTP client using cURL for Rust//tools/emacs-pkgscontains various useful Emacs libraries, for example:dottime.elprovides dottime in the Emacs modelinenix-util.elprovides editing utilities for Nix filesterm-switcher.elis an ivy-function for switching between vterm bufferstvl.elprovides helper functions for interacting with the TVL monorepo
//lisp/klatreprovides a grab-bag utility library for Common Lisp
User packages
Contributors to the repository have user directories under
//users, which can be used for
personal or experimental code that does not require review.
Some examples:
//users/grfn/xanthous: A (WIP) TUI RPG, written in Haskell.//users/tazjin/emacs: tazjin's Emacs & EXWM configuration//users/tazjin/finito: A persistent finite-state machine library for Rust.
Licensing
Unless otherwise stated in a subdirectory, all code is licensed under the MIT license. See LICENSE for details.
Contributing
If you'd like to contribute to any of the tools in here, please check out the contribution guidelines and our code of conduct.
IRC users can find us in #tvl on hackint, which is also
reachable via XMPP at #tvl@irc.hackint.org (sic!).
Hackint also provide a web chat.