Pretty Turtle

A pretty turtle syntax writer (including support for RDF-star)

Usage

import { write } from '@jeswr/pretty-turtle';

// Convert RDF/JS quads into a pretty turtle string
const str = await write(quads);

Options

The write function accepts an optional second parameter with configuration options:

interface Options {
  prefixes?: Record<string, string>;
  format?: string;
  compact?: boolean;
  isImpliedBy?: boolean;
  baseIri?: string;
  explicitBaseIRI?: boolean;
  ordered?: boolean;
}

format

Specifies the output format. Supported values:

• 'text/turtle' (default) - Standard Turtle format
• 'text/n3' - Notation3 format

// Convert RDF/JS quads into a Notation3 string
const str = await write(quads, {
  format: 'text/n3'
});

prefixes

A map of prefix names to their corresponding namespace URIs for compacting URIs in the output.

const str = await write(quads, {
  prefixes: {
    ex: "http://example.org/",
    foaf: "http://xmlns.com/foaf/0.1/",
    schema: "https://schema.org/"
  }
});

compact

When set to true, produces a more compact output by removing unnecessary whitespace and line breaks.

// Compact output
const str = await write(quads, {
  compact: true
});

baseIri

Sets the base IRI for the document, which can be used to resolve relative IRIs.

const str = await write(quads, {
  baseIri: "http://example.org/base/"
});

explicitBaseIRI

When set to true, explicitly writes the @base directive in the output even if a base IRI is provided.

const str = await write(quads, {
  baseIri: "http://example.org/base/",
  explicitBaseIRI: true
});
// Output will include: @base <http://example.org/base/> .

isImpliedBy

Used to opt in to using isImpliedBy syntax (<=) when in N3 mode.

const str = await write(quads, {
  format: 'text/n3',
  isImpliedBy: true
});

ordered

When set to true, the output will be deterministic with consistent ordering. This sorts prefixes, subjects, predicates, and objects alphabetically to ensure the same input always produces the same output.

// Ordered output - useful for consistent serialization
const str = await write(quads, {
  ordered: true
});

This is particularly useful for:

• Testing and comparing outputs
• Version control where you want consistent diffs
• Caching scenarios where deterministic output is important

Complete Example

import { write } from '@jeswr/pretty-turtle';

const str = await write(quads, {
  format: 'text/turtle',
  prefixes: {
    ex: "http://example.org/",
    foaf: "http://xmlns.com/foaf/0.1/"
  },
  baseIri: "http://example.org/base/",
  explicitBaseIRI: true,
  compact: false,
  ordered: true
});

License

©2023–present Jesse Wright, MIT License.