Julia 1.11 Highlights
After two alphas, two betas, and four release candidates, Julia version 1.11 has finally(!!!) been released. We want to thank all the contributors to this release and all the testers who helped find regressions and issues in the pre-releases. Without you, this release would not have been possible.
The full list of changes can be found in the NEWS file, but here we'll give a more in-depth overview of some of the release highlights.
Prior to Julia 1.11, Array was a special object in Julia. Operations like resizing and creation had to be done completely in C, which created overhead and made some of the code much harder to write and difficult for the compiler to optimize. Array also had some features that were unnecessary for some uses (e.g. resizing and multiple dimensions) which imposed a small cost. To fix this, in https://github.com/JuliaLang/julia/pull/51319, we added a new, lower level Memory type, which allowed re-implementing all of Array in Julia code on top of it. This moved much of the complexity around resizing and copying an array into pure Julia code. And it allowed a few important data types, that don’t need all of Array’s features (such as Dict), to avoid a small amount of overhead. This has led to some great performance improvements. For example, push! on Array is now roughly ~2x faster, and several types in Base now use slightly less memory.
In previous Julia versions, there was no "programmatic way" of knowing if an unexported name was considered part of the public API or not. Instead, the guideline was basically that if it was not in the manual then it was not public which was a bit underwhelming. To remedy that, there is now a public keyword in Julia that can be used to indicate that an unexported name is part of the public API. Whether a name is public or not can now be checked with the (public) method Base.ispublic(m::Module, name::Symbol), and this is for example used by the help system in the REPL to indicate if a documented name is non-public:
