libfyaml

chuckle Well most of that is due to 1.1 which has been deprecated god knows for how long. 1.2 does not have the 'Norway' problem any more. Tooting my own horn, this is how a modern YAML library looks like nowadays: https://github.com/pantoniou/libfyaml

libfyaml 1.0.0-alpha7 adds an opt-in transparent parse cache for repeated reads of stable YAML/JSON files. It is not making the parser itself hundreds of times faster. On a cache hit, libfyaml mmaps the generic arena and directly uses that instead of parsing the file. Due to the design of the generic subsystem it even avoids relocation and in 64bit systems with ASLR. Benchmark run using the python binding on AllPrintings.json sized 427.5 MB. - cache off: 16.98 s, +13.4 GB RSS - cold cache: 22.45 s, +13.4 GB RSS - hot cache: 35.9 ms, +1.0 MB RSS That is about 473x faster on the hot-cache path versus a normal parse, with a much smaller memory delta. Also note how the RSS is essentially zero; the generic data in the arena are not even faulted in. This is intended for startup/config/data-loading workloads where the same large YAML or JSON fil

libfyaml is a C library for YAML 1.2 parsing and emission. I have been working on it for several years as a parser/emitter library, and this alpha is the point where three additional interfaces are being released as public parts of the project. Part of the motivation for the work is that I think modern C libraries can offer more ergonomic APIs than is often assumed, if they actually use modern C features. C99 is old at this point, and using C11 and newer C2x-era features makes it possible to build interfaces that are still plain C, but are easier to use. You can do tThings like functional-flavored, Python-like data handling and typed serialization based on reflection. What is new in 1.0.0-alpha1: - a generic runtime for working with YAML values in C via fy_generic - a reflection subsystem for YAML to C and C to YAML seriali

libfyaml is a feature-complete YAML 1.2 parser/emitter written in C. It passes the entire official YAML test suite and focuses on high performance with zero-copy operation. What's new in v0.9.4: • Full native Windows support (MSVC, clang-cl, Clang) - all tests pass • Comment handling moved out of experimental - comments can now be reliably preserved and round-tripped GitHub: https://github.com/pantoniou/libfyaml Docs: https://pantoniou.github.io/libfyaml/ Happy to answer questions about the implementation or YAML parsing in general.

AFAIK, libfyaml[0] (not to be confused with libyaml) passes the 1.2 test suite, and if I remember correctly, it's currently the only YAML loader with that claim at the moment. The yaml.orf website also lists a bunch of implementations, with about 1/3 supporting 1.2. I'm guessing that the users of those libraries just happily hum along and we never hear from them! The issue is that downstream consumers of popular languages with a vocal community here on HN tend to just pull in libyaml, PyYAML being the major offender in my mind. [0]:https://github.com/pantoniou/libfyaml

> So this article is talking about YAML 1.1, while the other article is talking about YAML 1.2. Precisely. The article is really noticing quirks and limitations libyaml, the library doing the heavy lifting behind PyYAML, not YAML-the-spec proper. Granted, in practice, library limitations are probably what you want to know about. AFAIK, libfyaml[0] (not libyaml) is the most spec-compliant library around. It's a shame more downstream languages aren't using it. [0]:https://github.com/pantoniou/libfyaml