Release 2.4.0 - Sep 06, 2026 · hoc081098/dart_either

https://pub.dev/packages/dart_either/versions/2.4.0

Relocated flatMap, getOrElse, getOrHandle, handleError,
and handleErrorWith from Either instance members to exported generic extensions.
- Statically typed dot-call syntax and behavior are unchanged,
  while analyzer-valid widened receivers no longer fail at a covariant virtual
  method boundary.
- Selective imports must include the relevant extension type,
  and dynamic receivers no longer dispatch to these operations.
Split every value-operation extension exported by either_extensions.dart
into a method-named source file. This file split changes only the source
layout; public exports, call syntax, and behavior remain unchanged, so no
consumer migration is required for the split.

Fixed Either.parSequenceN and Either.parTraverseN with finite concurrency
so functions still waiting for a permit are not invoked after the first
observed Left, thrown error, or failed future.
- A Left is returned when it is observed first;
  an ordinary error observed first is propagated with its stack trace.
- Already-running functions remain non-cancellable and may finish their side effects.
A non-null maxConcurrent less than or equal to zero now throws an
ArgumentError synchronously, before inputs are traversed, the
parTraverseN mapper is called, or callbacks are invoked.
Errors thrown while iterating the input or invoking the parTraverseN
mapper now propagate synchronously instead of completing the returned future
with an error. No asynchronous operation callback is invoked if this input
preparation fails.

Full Changelog: 2.3.0...2.4.0