Release notes

The format is based on Keep a Changelog, and this project adheres to Semantic Versioning.

Version v1.4.2 - 2026-10-13

No public-facing changes in this version, only new FileCheck-based tests added (#204).

Improved performance on Julia v1.13 and later of loops after a check of the size of a FixedSizeArray argument, such as axes(a) == axes(b) || throw(...): size now loads all dimensions at once, so that LLVM can use the checked dimensions in the loop instead of reloading them. (#201, #202)

New public function FixedSizeArrays.wrap to construct a FixedSizeArray around an existing parent DenseVector (e.g. a Memory or a Vector) without copying it. (#196)
Package extension with MPI.jl: FixedSizeArrays (and SubArrays of them) can now be used directly as communication buffers in MPI operations, e.g. MPI.Send, MPI.Recv!, MPI.Bcast!, MPI.Allreduce! and MPI.Gatherv!, by defining MPI.Buffer(::FixedSizeArray) and the conversion to MPI.MPIPtr. Requires MPI.jl v0.20.28 or later. (#198)

BoundsErrorLight is now an alias for LightBoundsError from the LightBoundsErrors.jl package, instead of being a type defined in this package. As a consequence, the properties of the exception object and the error message have changed. (#176)
All out-of-bounds accesses to a FixedSizeArray going through checkbounds now throw LightBoundsError, not only those indexing with a single integer; the other cases used to throw BoundsError. (#175, #176)
The validation of the dimensions when constructing a FixedSizeArray is now implemented with the CheckedSizeProduct.jl package. Invalid dimensions still throw an ArgumentError, but with a single error message which includes the offending shape. (#89, #90)

isassigned(::FixedSizeArray, ::Int) now checks the bounds on the FixedSizeArray itself, instead of relying on the parent to do it, giving correct results also with underlying storage types which do not check bounds. (#188)
copy!(::FixedSizeVector, ::AbstractVector) now throws a descriptive ArgumentError when the axes of the two arrays do not match, instead of a MethodError caused by trying to call resize! on the destination. (#194, #195)

The package extensions were renamed from RandomExt and AdaptExt to FixedSizeArraysRandomExt and FixedSizeArraysAdaptExt, respectively, to avoid clashes with similarly named extensions in other packages. (#162)
Improved performance of iterating over a FixedSizeArray: constant propagation through iterate now allows the compiler to unroll loops over arrays with statically known size. (#158)
Improved performance of destructuring a FixedSizeArray with a slurping pattern (e.g. a, rest... = array), by adding a method to Base.rest. (#166)

Indexing a multidimensional FixedSizeArray with a single Colon (A[:]) now always returns a vector, instead of an array with the same shape as A. (#161)
Fixed type inference of collect_as in Julia v1.12 and later. (#160, #172)

Pkgextension with Adapt.jl, for converting other arrays to FixedSizeArray. (#149)

Initial release.