Visualize.Chart.Composite (Visualize v0.2.35)

A fragment whose content is a list of use sites, and how it becomes a design (spec/14 §19.6, D-103).

%{composite: %{
  uses: [%Visualize.Chart.Use{...}, ...],   # in stack order, the higher later
  vars: %{color_1: %{default: :series_1}}   # the composite's own variables
}}

Save writes structure: this is what the store holds. Flatten is a deployment verb: flatten/2 resolves every use through a store — ref → local → mask → bind — recursively where a use refers to another composite, and stacks the result into a flat design in §13's shape, with no ids and no uses. A composite that reaches itself through any chain of uses is refused as an extends cycle is (§3.5).

A ref the store no longer holds is a mask of everything at that site (§19.2); the design still flattens, and the missing ids are returned so a host that wants strictness has them.

Every site is placed by its kind (§19.6): a positional kind writes its key, a frame cascades into frame, a list kind appends by its own identity, and a name-keyed kind — style, scale, source, var — lands under the site's key. A name-keyed site with no key is not placed, and is reported as keyless beside missing.

Summary

Types

report()

What flatten/2 reports beside the design: every ref no store could find — a site's, by the site's id, or a reference inside the design, by its path — and every name-keyed site this composite holds that has no key to be declared under.

Functions

composite?(arg1)

Whether a fragment is a composite: one key, composite, holding uses.

decompose(document)

A flat document as sites, one kind each (spec/14 §18.12): its theme, its meta, its frame without the scales and axes, then one keyed site per style, scale, source and var, one site per mark, per label and per axis, in the order the document is read. flatten/2 of the result is the document again, version aside, which flatten writes. Each site comes with a label a person reads.

flatten(fragment, fetch)

A composite resolved through a store and stacked: a flat design (spec/14 §19.6).

place(contribution, use)

A site's contribution placed in the design by its kind (spec/14 §19.6): a wrapper body becomes the layer that declares it where the design keeps that kind — a name-keyed one under the site's key — and anything else cascades as it is.