Result.js

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Changelog ​

All notable changes to this project will be documented in this file.

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

1.2.0 - 2025-12-15 ​

Added ​

  • Validation methods:

    • Result.validate() - Create Result by validating value with predicate
    • Result.fromNullable() - Create Result from nullable values
    • Result.isResult() - Type guard for Result instances
    • isOkAnd() / isErrAnd() - Validate Result with predicates

  • Collection methods:

    • Result.allSettled() - Collect all Results without failing
    • Result.any() - Return first Ok or all errors
    • Result.partition() - Separate successes and failures
    • Result.values() / Result.errors() - Extract values or errors

  • Transformation methods:

    • filter() - Filter Ok values by predicate
    • zip() - Combine two Results into tuple

  • Async methods:

    • mapAsync(), mapErrAsync(), mapOrAsync(), mapOrElseAsync()
    • andThenAsync(), andAsync(), orAsync(), orElseAsync()

  • Other methods:

    • contains() / containsErr() - Check for specific values/errors
    • inspectErr() - Side effects on errors
    • toJSON() - JSON conversion

  • VitePress documentation with comprehensive JSDoc comments

Changed ​

  • BREAKING: Complete rewrite with Ok and Err classes
  • BREAKING: Result.sequence() → Result.all()
  • BREAKING: Result.is() → Result.isResult()
  • BREAKING: Errors now throw with cause property
  • Module exports use .js extension (was .mjs)
  • Homepage now points to documentation site
  • types script renamed to typecheck

Removed ​

  • BREAKING: Result.sequenceAsync() (use async methods instead)
  • BREAKING: inspectOk() (use match() or inspect() instead)

1.1.0 - 2025-11-20 ​

Added ​

  • Result.sequence() - Combines multiple Results into single Result with array of values
  • Result.sequenceAsync() - Async version of sequence for Promise-based Results
  • Result.fromPromise() - Converts Promises to Results, catching rejections
  • Result.fromTry() - Wraps functions that may throw into Results

Changed ​

  • unwrap() now throws the original error directly instead of wrapping it
  • expect() now includes the original error as cause for better error tracing

1.0.0 - 2025-11-20 ​

First stable version for production use.