failure_kit 1.0.0

HTTP-client agnostic error handling for Dart/Flutter — Either pattern, typed Failures, and a pluggable mapper chain.

Changelog

1.0.0

Initial pub.dev release.

Features

• Either<L, R> — sealed Left / Right with map, mapAsync, then, thenAsync, fold, getOrElse, swap, tryCatch, tryExcept, cond, condLazy.
• Failure — abstract base class. User-defined subclasses are first-class citizens (route to when(custom:)).
• Built-in failure types: ServerFailure (with statusCode and raw data), NoInternetFailure, TimeoutFailure, CancellationFailure, ParsingFailure, UnknownFailure.
• FailureMapper typedef — Failure? Function(Object, StackTrace). Return null to delegate to the next mapper in the chain.
• FailureMapperChain — interceptor-style chain. First non-null result wins. Falls back to BaseFailureMapper.
• FailureGuard mixin — wraps async actions in Either<Failure, T> via call(...).

Notes

• Package is HTTP-client agnostic and has no dio dependency. See example/dio_integration.dart for a copy-paste Dio mapper.