@tabnas/semver

A Tabnas grammar plugin that parses Semantic Versioning 2.0.0 version strings into their five parts, exactly as the specification defines them. The parser is the specification's own grammar, compiled from ABNF by @tabnas/abnf at build time, so the plugin installs a ready rule set and needs no compiler at run time.

Install

npm install @tabnas/parser @tabnas/semver

@tabnas/parser is a peer dependency, and the only one.

One example

The plugin installs on a bare Tabnas engine:

import { Tabnas } from '@tabnas/parser'
import { Semver, compare, format } from '@tabnas/semver'

const tn = new Tabnas().use(Semver)

tn.parse('1.2.3-alpha.1+build.5')
// => { major: 1, minor: 2, patch: 3, prerelease: ['alpha', 1], build: ['build', '5'] }

compare(tn.parse('1.0.0-alpha'), tn.parse('1.0.0')) // => -1
format(tn.parse('1.2.3+sha.5114f85'))               // => '1.2.3+sha.5114f85'

Build the instance once and reuse it: installing the grammar is the expensive part.

Documentation

Full documentation follows the Diátaxis framework:

• Tutorial. A guided first parse, start to finish.
• How-to guide. Short recipes for individual tasks.
• Reference. The public API, the value shape, and the complete syntax accepted.
• Concepts. How the plugin turns the specification's grammar into a parser, and why.

For the Go port, see ../go/README.md.

Grammar

The grammar is defined in the top-level semver-grammar.abnf. gen-grammar.js (npm run gen-grammar) compiles it into semver-grammar.json, the engine's rule set, and copies that file into this package (src/semver-grammar.json) and the Go and Rust ports; the plugin installs it. embed-grammar.js embeds the ABNF text itself during the build, exported as grammar for tooling that wants it.

License

Copyright (c) 2026 Richard Rodger and other contributors, MIT License.