ai-agent

proposal-pattern-matching

Name: proposal-pattern-matching
Author: tc39

Pattern matching syntax for ECMAScript

5,804 stars+3★ this week90 forksHTMLUpdated 10/5/2025100% free · open source

What it does

Proposal-pattern-matching allows you to use pattern matching syntax in ECMAScript, making it easier to handle complex data structures and conditional logic in your code

When to use it

•When working with complex, nested data structures and you need to handle different cases based on the structure
•When you want to simplify your code by replacing long chains of if-else statements with a more expressive and concise syntax
•When you're working with functional programming concepts and need a more declarative way of handling data transformations

Ready-to-paste prompt

match ([x, y]) { case [1, 2] => console.log('matched [1, 2]'); case [3, 4] => console.log('matched [3, 4]'); case _ => console.log('default case'); }

Heads up: Make sure you're using a compatible version of Node.js (14 or higher) and Babel (7.10 or higher), as the proposal-pattern-matching syntax is not supported in older versions

Saves to your device

Use with Claude

New

Skip the builder — one click puts this in Claude, Cursor, Antigravity and more.

✅ Light setup

Installs with a command or two; your AI agent can do it for you.

Try it instantly — no install

Claude Code

mkdir -p ~/.claude/skills/proposal-pattern-matching && curl -fsSL https://workflowstacks.com/api/skills/proposal-pattern-matching/claude-skill -o ~/.claude/skills/proposal-pattern-matching/SKILL.md

Open in another AI app

Opens the app with this repo with the prompt ready to go — no copy-paste needed.

Connect the whole catalog (MCP)

claude mcp add --transport http workflowstacks https://workflowstacks.com/api/mcp

Adds a WorkflowStacks connector to Claude Code: search and load any skill here by chatting.

How proposal-pattern-matching works

Codeflow

Free to inspect

Proposal-pattern-matching is a small HTML project (~2.8k lines across 2 code files). Setup is light: install Node.js, run one command. Last commit 12 months ago, MIT license, no tests found.

Size

Small codebase

~2.8k lines · 2 code files · 23 min skim

Setup

Light setup

Install Node.js, run one command.

Runs on

Node.js

No API keys detected

HTML 76%JavaScript 19%CSS 5%

Where to start reading

1
README.md
Start here — what it does and how to install it
2
package.json
Dependencies and the commands it exposes

What's in each folder

assets/Images & static assets17 files

.github/CI / automation (GitHub Actions)1 files

READMENo tests foundThin docsCI checksMIT licenseLast update 12 mo ago

Use with Claude

New

Skip the builder — one click puts this in Claude, Cursor, Antigravity and more.

✅ Light setup

Installs with a command or two; your AI agent can do it for you.

Try it instantly — no install

Claude Code

mkdir -p ~/.claude/skills/proposal-pattern-matching && curl -fsSL https://workflowstacks.com/api/skills/proposal-pattern-matching/claude-skill -o ~/.claude/skills/proposal-pattern-matching/SKILL.md

Open in another AI app

Opens the app with this repo with the prompt ready to go — no copy-paste needed.

Connect the whole catalog (MCP)

claude mcp add --transport http workflowstacks https://workflowstacks.com/api/mcp

Adds a WorkflowStacks connector to Claude Code: search and load any skill here by chatting.

Quick Actions

Details

Creator

tc39

Language

HTML