Fable 5.0.0-alpha.15 released!

NewsBot · 19 November 2025 13:19

Fable 5.0.0-alpha.15 has been released.

Added

[TS] Added support for erasableSyntaxOnly in TypeScript (by @ncave)

[All] Added some default System exception implementations (by @ncave)

[All] Added ofOption/toOption/ofValueOption/toValueOption (by @ncave)

[Python] Added Decorate attribute to add Python decorators to classes (by @dbrattli)

[Python] Added ClassAttributes attribute to control Python class generation (@dbrattli)

[Python] Added support for Python 3.14 (by @dbrattli)

Changed

[JS/TS] Replace the deprecated substr method with slice (by @Thorium)

Fixed

[TS] Fix ObjectExpr tests with multiple interfaces (by @ncave)

[TS] Fix ObjectExpr abstract base constructor type (by @ncave)

[JS/TS] Fix #4240 Missing DateTime constructor (by @ncave)

[PHP] Fix php import extensions (by @MangelMaxime)

[TS] Fix #3973 Typescript imports file extension (by @ncave)

[TS] Fix support for abstract classes and members (by @ncave)

[TS] Fix getters, setters, indexers in interfaces (by @ncave)

[TS] Enable typedArrays flag usage for TypeScript (by @ncave)

[All] Fix #4221 Fable.Type union case arg names (by @ncave)

[All] Erase Nullable Reference Types to inner type (by @ncave)

[Python] Improve Python (e.g. Pydantic) interop (by @dbrattli)

[JS/TS] Fix comparers for non-nullable types (by @ncave)

[Rust] Fix curried object expression getters (by @ncave)

[Rust] Fix compiler-generated generic args (by @ncave)

[All] Fixed #4041 missing unit argument (by @ncave)

[JS/TS/Python] Fixed eq comparer mangling (by @ncave)

[All] Fix all BitConverter return types (by @ncave)

[TS] Don’t cast union case types to any (by @ncave)

[JS/TS] Fix Dictionary.ICollection.Remove (by @ncave)

[TS/Dart] Fixed optional parameter types (by @ncave)

[TS] Initialize un-initialized variables (by @ncave)

[JS/TS] Replace Error with Exception (by @ncave)

[All] Fix MSBuildResolver to include define when restoring the project (by @MangelMaxime)

Link: Release 5.0.0-alpha.15 · fable-compiler/Fable · GitHub