light_result 0.2.1

A lightweight, zero-dependency functional error handling package for Dart 3. Built with sealed classes and pattern matching.

0.2.1

• Expanded Dart SDK support to >=3.0.0 <4.0.0.
• Relaxed the lints development dependency to support the wider SDK range.
• Excluded local progress notes and generated files from published archives.

0.2.0 — Breaking: Success/Failure Rename

Breaking Changes

• Renamed core types: Left → Failure, Right → Success.
• Renamed getters: isLeft → isFailure, isRight → isSuccess.
• Renamed methods: mapLeft → mapFailure, getLeftOrNull → getFailureOrNull, tapLeft → tapFailure.
• Renamed async extensions: thenMapLeft → thenMapFailure, thenTapLeft → thenTapFailure.
• Renamed matchers: isLeft → isFailure, isRight → isSuccess, isLeftWith → isFailureWith, isRightWith → isSuccessWith.
• Renamed utility class: Failure → AppError (to avoid conflict with the new Failure sealed subclass).
• Removed Result.left() and Result.right() factory constructors (use Result.failure() / Result.success()).

Migration

Deprecated Left<L, R> and Right<L, R> type aliases are provided for gradual migration. See README for full migration table.

Why?

Dart developers coming from Rust/Kotlin expect Ok/Err or Success/Failure terminology. The old Left/Right naming (Haskell/Scala Either convention) was a barrier to adoption. The new names are self-documenting — no mnemonic needed.

0.1.2

• Docs: Rewrote README with motivation section and real-world comparisons.
• Docs: Rewrote example with 6 practical scenarios (login, API, validation, cache, Option, async chaining).

0.1.1

• Fix: LICENSE file now uses standard MIT format recognized by pub.dev.
• Fix: Resolved unintended_html_in_doc_comment warning in TaskResult docs.
• Added Unit type for void-returning Result operations.
• Added Either<L, R> type alias for fpdart/dartz migration.

0.1.0

• Initial release.
• Result<L, R> sealed class with Left and Right subclasses.
• Option<T> sealed class with Some and None subclasses.
• Full pattern matching support with exhaustive checking.
• Functional chaining: map, mapLeft, flatMap, fold, getOrElse, tap, tapLeft, swap, filter.
• Result.guard() and Result.guardAsync() for safe exception wrapping.
• Result.combine() and Result.waitAll() for combining multiple results.
• TaskResult and TaskOption extensions for async chaining without intermediate await.
• Type aliases: ResultOf, StringResult, AppResult, AsyncResult, AsyncResultOf.
• Failure base class for typed error hierarchies.
• Test matchers: isRight, isLeft, isRightWith, isLeftWith, isSome, isNone, isSomeWith.