API Reference

The Loom Standard Library

Welcome to the technical reference for the Loom engine. This section details the modules, functions, and types available in the package.

info

If you are looking for conceptual guides or tutorials, please check the Concepts or Showcase sections.

Modules Overview

Loom is organized into several modules to keep the namespace clean.

Module	Description
Engine	The weave loop, construct-loom, and lifecycle hooks.
Motifs	The component constructors: motif, content-motif, data-motif.
Query	Utilities for searching, filtering, and aggregating signals.
Mutator	Utilities for performing immutable updates on the Context.
Guards	Assertion functions to enforce document architecture.
Matcher	Schema validation and pattern matching utilities.
Utilities	Helpers for data manipulation (collection) and path inspection (path).

The loom Namespace

While you typically use construct-loom to create your own library instance, the static utilities are always available directly from the package.

#import "@preview/loom:0.1.0"

// 1. Core Constructors
#let (weave, motif, ..) = loom.construct-loom(<my-lib>)

// 2. Static Utilities (Used inside measure/scope)
#loom.query.select(..)
#loom.mutator.batch(..)
#loom.guards.assert-inside(..)
#loom.matcher.match(..)
#loom.collection.get(..)

Pro Tip: Destructuring

You can destructure the engine components directly during construction to keep your code clean: #let (weave, motif) = loom.construct-loom(<id>)

Common Types

Throughout this reference, we use the following type definitions:

• Context: dictionary The immutable state object passed down from parent to child.
• Signal: dictionary A data packet emitted by a component during the measure phase. It bubbles up to the parent.
• Motif: function A Loom component. Technically, it is a standard Typst function that returns a (key, payload) tuple.
• Body: content | array The content passed to a component.