TypeScript

AsciiChem or SMILES — try something your colleagues useCC(=O)OC1=CC=CC=C1C(=O)O

·Ruby

asciichem

gem install asciichemReference implementation.

·TypeScriptyou are here

asciichem-ts

npm install asciichemPowers this page.

·Python

asciichem-py

pip install asciichem-pyZero runtime deps.

npm install asciichem

Published to npm via trusted publishing (OIDC, no stored credentials) with SLSA provenance attestations — see the provenance on npm.

Quick start

import { parse, parseSmiles, parseMolfile, renderMathml } from "asciichem";

// Same model as the Ruby reference — every format the gem emits, in
// the browser or Node.
parse("2H_2 + O_2 ->[heat] 2H_2O").toText();

parse("C1-C-C-C-C-C1").toStructuralSvg();  // cyclohexane hexagon

// Structures from databases, straight into the model
const aspirin = parseSmiles("CC(=O)OC1=CC=CC=C1C(=O)O");
aspirin.toStructuralSvg();
aspirin.toSmiles();           // deterministic writer — round-trips exactly

parseMolfile(v2000Text);      // coordinates preserved for rendering

// MathML goldens — byte-identical with the reference implementation.
console.log(renderMathml(parse("^14C")));

Claimed levels

Parse / reject · L0 emission · L1 text · L2 MathML · SMILES · molfile — 100% of the shared corpus. See the Implementations matrix for the full table.

What you get here, not elsewhere

This is the package that powers this site’s live renderer and every diagram on this page. Highlights:

• Runs in the browser — the live playground uses it directly. No server, no build step beyond import.
• Peggy parser — a faithful port of the reference grammar, with the same atoms, same precedence, same round-trip guarantees. Zero runtime dependencies.
• All formats in TS — Text, typographic SVG, 2D structural SVG, presentation MathML (L2 goldens), wire JSON, SMILES writer, molfile reader/writer.
• Three-pane live diff (above) — type once, three identical outputs across Ruby / TypeScript / Python, the live demonstration of the single-contract rule.

Repository

github.com/asciichem/asciichem-ts — powers this page.