abseil-cpp
outcome
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abseil-cpp | outcome | |
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54 | 9 | |
13,878 | 662 | |
2.1% | - | |
9.5 | 7.4 | |
6 days ago | 18 days ago | |
C++ | C++ | |
Apache License 2.0 | 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.
abseil-cpp
- Sane C++ Libraries
- Open source collection of Google's C++ libraries
- Is Ada safer than Rust?
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Appending to an std:string character-by-character: how does the capacity grow?
Yeah, it's nice! And Abseil does it, IFF you use LLVM libc++.
https://github.com/abseil/abseil-cpp/blob/master/absl/string...
The standard adopted it as resize_and_overwrite. Which I think is a little clunky.
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Shaving 40% Off Google’s B-Tree Implementation with Go Generics
This may be confusing to those familiar with Google's libraries. The baseline is the Go BTree, which I personally never heard of until just now, not the C++ absl::btree_set. The benchmarks aren't directly comparable, but the C++ version also comes with good microbenchmark coverage.
https://github.com/google/btree
https://github.com/abseil/abseil-cpp/blob/master/absl/contai...
- Faster Sorting Beyond DeepMind’s AlphaDev
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“Once” one-time concurrent initialization with an integer
An implementation of call_once that accommodates callbacks that throw: https://github.com/abseil/abseil-cpp/blob/master/absl/base/c...
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[R] AlphaDev discovers faster sorting algorithms
I wouldn't say it's that cryptic. It's just a few bitwise rotations/shifts/xor operations.
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Deepmind Alphadev: Faster sorting algorithms discovered using deep RL
You can see hashing optimizations as well https://www.deepmind.com/blog/alphadev-discovers-faster-sort..., https://github.com/abseil/abseil-cpp/commit/74eee2aff683cc7d...
I was one of the members who reviewed expertly what has been done both in sorting and hashing. Overall it's more about assembly, finding missed compiler optimizations and balancing between correctness and distribution (in hashing in particular).
It was not revolutionary in a sense it hasn't found completely new approaches but converged to something incomprehensible for humans but relatively good for performance which proves the point that optimal programs are very inhuman.
Note that for instructions in sorting, removing them does not always lead to better performance, for example, instructions can run in parallel and the effect can be less profound. Benchmarks can lie and compiler could do something differently when recompiling the sort3 function which was changed. There was some evidence that the effect can come from the other side.
For hashing it was even funnier, very small strings up to 64 bit already used 3 instructions like add some constant -> multiply 64x64 -> xor upper/lower. For bigger ones the question becomes more complicated, that's why 9-16 was a better spot and it simplified from 2 multiplications to just one and a rotation. Distribution on real workloads was good, it almost passed smhasher and we decided it was good enough to try out in prod. We did not rollback as you can see from abseil :)
But even given all that, it was fascinating to watch how this system was searching and was able to find particular programs can be further simplified. Kudos to everyone involved, it's a great incremental change that can bring more results in the future.
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Backward compatible implementations of newer standards constructs?
Check out https://abseil.io. It offers absl::optional, which is a backport of std::optional.
outcome
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How to define API stability for a C++ library?
https://github.com/ned14/outcome/tree/develop/abi-compliance uses both in a CI pass to ensure Outcome never changes anything which breaks either API or ABI with earlier versions.
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What are some cool modern libraries you enjoy using?
outcome and/or expected
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Outcome enters sustaining phase, goes ABI stable
A "Sample Usage" appears on the front page of the docs: https://ned14.github.io/outcome/
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Does Anyone Use Boost Outcome?
I recently came across boost outcome as I was searching for a better error handling method. It took me a minute to get a hang of it but now I love it. After creating my own policy and a few aliases for easier use.
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Is this error handling strategy good?
std::optional and std::variant can be a bit awkward to use in this scenario, though. Consider a dedicated type like boost::outcome (standalone versions) or one of the implementations of the proposed std::expected.
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Modern C++ "result" type based on Swift / Rust
Minimum possible compile time impact is a key goal of https://github.com/ned14/outcome. We ship a single header edition which only includes the low impact standard headers as listed at https://github.com/ned14/stl-header-heft. We also don't use union storage for non-TC non-MB types in order to avoid complex metaprogramming execution by the compiler per instantiation.
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C++ Memory Safety
It's really weird that I wrote the above, and then this bug was reported to Outcome: https://github.com/ned14/outcome/issues/244. Here is my exact complaint about lack of lifetime tracking in C++.
What are some alternatives?
Folly - An open-source C++ library developed and used at Facebook.
leaf - Lightweight Error Augmentation Framework
Boost - Super-project for modularized Boost
C++ Format - A modern formatting library
spdlog - Fast C++ logging library.
Experimental Boost.DI - C++14 Dependency Injection Library
Qt - Qt Base (Core, Gui, Widgets, Network, ...)
stb - stb single-file public domain libraries for C/C++
EASTL - Obsolete repo, please go to: https://github.com/electronicarts/EASTL
Serial Communication Library - Cross-platform, Serial Port library written in C++
BDE - Basic Development Environment - a set of foundational C++ libraries used at Bloomberg.
ZXing - ZXing ("Zebra Crossing") barcode scanning library for Java, Android