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Unwrap OR

A TypeScript implementation of Rust's Option and Result types.

_{no deps | tree-shakeable | side-effect free}

It is a playground library that closely mirrors Rust's Option and Result API. While created primarily for fun and learning, it's robust enough for real-world applications. It allows for safer, more expressive handling of optional values through a monadic interface. Snake_case is used for the plausibility of the original.

Use it to:

• eliminate null checks
• make optional logic explicit
• chain transformations on values that might not exist
• handle errors gracefully

The name unwrap-or is a reference to the unwrap_or method in the Option/Result types and a combination of the first letters "-OR" of two monads for Option and Result types. It also relfects the logical OR operation reflecting two possible states.

Installation

Via deno:

deno add jsr:@lab/unwrap-or

You can also use your favorite package manager:

# pnpm
pnpm i jsr:@lab/unwrap-or

# npm
npx jsr add @lab/unwrap-or

# bun
bunx jsr add @lab/unwrap-or

# yarn
yarn add jsr:@lab/unwrap-or

Overview

See the documentation for unwrap-or usage, module specifications and API/methods details:

• Option
• Result

Inspirations

• fnts - minimal functional programming utilities for TypeScript & JavaScript inspired by the programming language Haskell.

• ts-expression - pair constructor, binary representation, a minimal implementation of Lisp's symbolic expressions (s-expressions) for TypeScript.

License

Made by a human being, not LLM.

Copyright © 2025 Roman Hnatiuk

Licensed under MIT.