sixten
Cap'n Proto
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sixten | Cap'n Proto | |
---|---|---|
5 | 66 | |
748 | 11,180 | |
- | 1.6% | |
1.8 | 9.2 | |
over 3 years ago | 5 days ago | |
Haskell | C++ | |
BSD 3-clause "New" or "Revised" License | GNU General Public License v3.0 or later |
Stars - the number of stars that a project has on GitHub. Growth - month over month growth in stars.
Activity is a relative number indicating how actively a project is being developed. Recent commits have higher weight than older ones.
For example, an activity of 9.0 indicates that a project is amongst the top 10% of the most actively developed projects that we are tracking.
sixten
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What do Haskellers think about Rust?
Immutable data structures don't necessarily require more memory: they can avoid deep copies. They are also automatically thread safe without expensive (slow) locking mechanisms. They also don't necessarily reduce cache locality. The reduced cache locality in the case of Haskell (I think) mainly comes from the representation of objects in its implementation (improved STG) which uses extensive boxing and jumps that hinder both spatial and temporal locality (require review/comment from GHC/Computer Architecture experts, take it with a grain of salt). Objects can be much more efficiently represented if not for the need to implement lazy (call-by-need) semantics. See sixten and futhark for examples.
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Not well known programming languages with interesting features?
[Sixten](https://github.com/ollef/sixten): functional programming with unboxed data by default.
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Tree Sitter and the Complications of Parsing Languages
I can't answer this well and don't know of any resources, but I have seen it before in the parser for sixten:
https://github.com/ollef/sixten/blob/60d46eee20abd62599badea85774a9365c81af45/src/Frontend/Parse.hs#L458
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What languages have bit struct / field constructs?
Sixten is a language that allows precise control over memory layout of algebraic data types.
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Designing a language where all types are memcpy/blittable.
For something more peripherally related, check out Sixten. Its focus is on using unboxed value representations, which is in spirit close to what you are proposing, and some of its ideas might be good inspiration.
Cap'n Proto
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Mysterious Moving Pointers
Yeah I pretty much only use my own alternate container implementations (from KJ[0]), which avoid these footguns, but the result is everyone complains our project is written in Kenton-Language rather than C++ and there's no Stack Overflow for it and we can't hire engineers who know how to write it... oops.
[0] https://github.com/capnproto/capnproto/blob/v2/kjdoc/tour.md
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Show HN: Comprehensive inter-process communication (IPC) toolkit in modern C++
- may massively reduce the latency involved.
Those sharing Cap'n Proto-encoded data may have particular interest. Cap'n Proto (https://capnproto.org) is fantastic at its core task - in-place serialization with zero-copy - and we wanted to make the IPC (inter-process communication) involving capnp-serialized messages be zero-copy, end-to-end.
That said, we paid equal attention to other varieties of payload; it's not limited to capnp-encoded messages. For example there is painless (<-- I hope!) zero-copy transmission of arbitrary combinations of STL-compliant native C++ data structures.
To help determine whether Flow-IPC is relevant to you we wrote an intro blog post. It works through an example, summarizes the available features, and has some performance results. https://www.linode.com/blog/open-source/flow-ipc-introductio...
Of course there's nothing wrong with going straight to the GitHub link and getting into the README and docs.
Currently Flow-IPC is for Linux. (macOS/ARM64 and Windows support could follow soon, depending on demand/contributions.)
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Condvars and atomics do not mix
FWIW, my C++ toolkit library, KJ, does the same thing.[0]
But presumably you could still write a condition predicate which looks at things which aren't actually part of the mutex-wrapped structure? Or does is the Rust type system able to enforce that the callback can only consider the mutex-wrapped value and values that are constant over the lifetime of the wait? (You need the latter e.g. if you are waiting for the mutex-wrapped value to compare equal to some local variable...)
[0] https://github.com/capnproto/capnproto/blob/e6ad6f919aeb381b...
- Cap'n'Proto: infinitely faster than Protobuf
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I don’t understand zero copy
The second one is to encode data in such a way that you can read it and operate on it directly from the buffer. You write data in a layout that is the same, or easily transformed as types in memory. To do that you usually need to encode with a known schema, only Sized types to efficiently compute fields locations as offsets in the buffer, and you usually represent pointers as offset into the encode. You can look at capnproto protocol for instance https://capnproto.org/
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OpenTF Renames Itself to OpenTofu
Worked well for Cap'n Proto (the cerealization protocol)! https://capnproto.org/
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A Critique of the Cap'n Proto Schema Language
With all due respect, you read completely wrong.
* The very first use case for which Cap'n Proto was designed was to be the protocol that Sandstorm.io used to talk between sandbox and supervisor -- an explicitly adversarial security scenario.
* The documentation explicitly calls out how implementations should manage resource exhaustion problems like deep recursion depth (stack overflow risk).
* The implementation has been fuzz-tested multiple ways, including as part of Google's oss-fuzz.
* When there are security bugs, I issue advisories like this:
https://github.com/capnproto/capnproto/tree/v2/security-advi...
* The primary aim of the entire project is to be a Capability-Based Security RPC protocol.
- Cap'n Proto: serialization/RPC system – core tools and C++ library
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Sandstorm: Open-source platform for self-hosting web app
I like how they use capability-based security [0] and use Cap'n Proto protocol. This is another technology that is slow to get broad adoption, but has many things going for when compared to e.g. Protocol Buffers (Cap'n Proto is created by the primary author of Protobuf v2, Kenton Varda).
[0] https://sandstorm.io/how-it-works#capabilities
[1] https://capnproto.org
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Flatty - flat message buffers with direct mapping to Rust types without packing/unpacking
Related but not Rust-specific: FlatBuffers, Cap'n Proto.
What are some alternatives?
atom-focus-mode - Atom editor extension - fades editor content and highlights only the lines you are working on
gRPC - The C based gRPC (C++, Python, Ruby, Objective-C, PHP, C#)
tree-hugger - A light-weight, extendable, high level, universal code parser built on top of tree-sitter
Protobuf - Protocol Buffers - Google's data interchange format
pony-tutorial - :horse: Tutorial for the Pony programming language
FlatBuffers - FlatBuffers: Memory Efficient Serialization Library
felix - The Felix Programming Language
ZeroMQ - ZeroMQ core engine in C++, implements ZMTP/3.1
vscode-theme-alabaster-dark - Dark version of alabaster ported from https://github.com/tonsky/sublime-scheme-alabaster
Apache Thrift - Apache Thrift
ante - A safe, easy systems language
MessagePack - MessagePack serializer implementation for Java / msgpack.org[Java]