Chris Tate 1856713700 Represent unions of classes as the instance pointer itself
A union of two or more class arms and at most two unit arms (`A | B`,
`A | B | undefined`, sum types over classes) now holds the instance
pointer instead of a reference-counted %ScrUnion box, as unions of
records already do. NULL and the null sentinel encode the unit arms.

The arm of a value is the arm whose preorder interval holds the
instance's class id. On 64-bit targets, hierarchy members already keep
their class id in the high half of the rc word, or in the 32-bit header
of ProgramLifetime classes. A standalone class that is an arm of such a
union now keeps its id the same way and counts in the low half; the
count reaches the immortal all-ones value instead of wrapping, as for
hierarchy members.

Each union has a tag helper that narrowing checks inline. Unions over
the same classes share one retain, release and trace: retain and
release use the shared 32-bit count, and only a release of the last
reference dispatches on the arm to that class's release. Unions over
ProgramLifetime classes retain and release nothing. When one arm
carries a collector header, every class of every arm's hierarchy does.

Arms may not extend one another, and must all be compact or all keep
the rc word, and all be ProgramLifetime classes or none. 32-bit
targets, library builds, lifetime-region programs, debug builds, and
unions used as Map keys or Set elements keep boxes.
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scriptc

Vercel Labs Experiment npm version: scriptc License: Apache-2.0 npm downloads per month: scriptc

scriptc compiles TypeScript and JavaScript to native executables and WebAssembly. It uses the types checked by the TypeScript compiler to generate machine code, and the output runs without Node.js installed. npm packages your program imports compile along with it. Code scriptc can't compile is reported at build time with a diagnostic and, where available, a rewrite hint.

scriptc is experimental and supports a subset of JavaScript, TypeScript, and Node.js APIs. Run scriptc coverage on an existing program to see how much of it compiles, and see the limitations and Node.js compatibility reference for details.

Installation

Install with Node.js 24 or later and npm:

$ npm install -g scriptc

The installed compiler runs natively on macOS, Linux, and Windows. Node.js is needed only to install it and to run WASI modules with scriptc run. Standalone compiler archives are also available from GitHub Releases.

Building executables requires a linker and the platform SDK or sysroot. See the quickstart for prerequisites and platform support for host requirements, cross-compilation, and WebAssembly.

Build a program

Create hello.ts:

const who = process.argv.length > 2 ? process.argv[2] : "world";
console.log(`hello, ${who}`);

scriptc run compiles the file and runs the result:

$ scriptc run hello.ts
hello, world

scriptc build writes an executable:

$ scriptc build hello.ts -o hello >/dev/null
$ ./hello scriptc
hello, scriptc

These examples use POSIX shell syntax. On Windows, build hello.exe and run it with .\hello.exe.

Use scriptc coverage hello.ts to check what compiles before you build. See coverage reports for details.

Use Node APIs

Supported Node APIs compile to the native runtime. For example, server.ts:

import { createServer } from "node:http";

const server = createServer((req, res) => {
  res.setHeader("content-type", "application/json");
  res.end(JSON.stringify({ path: req.url }));
});

server.listen(8080, () => {
  console.log("listening on http://localhost:8080");
});
$ scriptc build server.ts -o server >/dev/null
$ ./server
listening on http://localhost:8080

Use npm packages

npm packages compile into the executable with your code, so it doesn't read node_modules at runtime.

Create cli.ts:

import pc from "picocolors";

console.log(pc.green("hello from scriptc"));
$ npm install picocolors
$ scriptc build cli.ts -o cli >/dev/null
$ ./cli
hello from scriptc

Package support is partial. See npm dependencies for which packages compile and how to check them.

Documentation

Contributing

See CONTRIBUTING.md for source setup, testing, native artifact builds, and docs development.

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Description
GitHub Trending: vercel-labs/scriptc
Readme Apache-2.0
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C 23.4%
JavaScript 7.9%
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