API reference

Functions

buildFormFromSchema(schema, initial?)

Builds a typed FormGroup from a root nodeGroup schema.

function buildFormFromSchema<S extends NodeGroup>(
  schema: S,
  initial?: Record<string, unknown> | null,
): DFormGroup<S>;

Parameter	Type	Description
schema	NodeGroup	The root schema. Author it with defineSchema to keep inference.
initial	object | null	Optional seed values, keyed by the schema’s children keys. Each control is seeded from its matching slice, falling back to the node’s default.

Returns a FormGroup whose keys and control value types are inferred from schema.

const form = buildFormFromSchema(profileSchema, { firstName: 'Ada' });

defineSchema(schema)

Identity helper that captures a schema literal with its exact type while checking it against NodeGroup. Use it (or satisfies NodeGroup) so buildFormFromSchema can infer a typed form. See Typed schemas.

function defineSchema<const S extends NodeGroup>(schema: S): S;

buildControl(node, initial?)

Builds the AbstractControl for a single node — a FormControl, FormArray, or nested FormGroup depending on node.kind. Most code uses buildFormFromSchema; reach for buildControl to build one non-root node.

function buildControl<T extends NodeType>(
  node: T,
  initial?: unknown | null,
): DFormControl<T>;

Components

<nff-dynamic-recursive-form>

DynamicRecursiveFormComponent — renders a schema against a FormGroup. Import it into your standalone component’s imports.

<nff-dynamic-recursive-form
  [schema]="schema"
  [formGroup]="form"
  [editable]="true"
/>

Input	Type	Default	Description
schema	NodeGroup	—	Required. The schema to render.
formGroup	FormGroup	new empty group	The form to bind to — pass the result of buildFormFromSchema(schema).
initialValue	object	—	Optional seed value applied on init. Prefer seeding via buildFormFromSchema(schema, initial).
editable	boolean	false	Whether fields start editable. Each group also has an edit toggle.
title	string	—	Overrides the header title of the rendered group.

Note

Always pass a formGroup built from the same schema with buildFormFromSchema. Rendering with [schema] alone binds the fields to a throwaway group and the values won’t reach your form.

<nff-config-editor>

ConfigEditorComponent — a tree/detail editor for large configs. The structure (containers, lists, groups) is a tree on the left; selecting a node shows that node’s leaf fields for editing on the right. Binds to the same FormGroup as the form component.

<nff-config-editor [schema]="schema" [formGroup]="form" />

Input	Type	Default	Description
schema	NodeGroup	—	Required. The schema to edit.
formGroup	FormGroup	—	Required. The form from buildFormFromSchema(schema).
editable	boolean	true	Whether the detail fields are editable.

Types

The schema model. See the Schema reference for every property.

Type	Description
NodeGroup	A group of fields (object). The root of a schema.
Leaf	A single scalar field. Union of LeafString, LeafNumber, LeafBoolean, LeafEnum.
LeafList	A list of scalar fields.
NodeGroupList	A list of groups.
NodeChoice	A discriminated selection (cases); in the form value the selection is { __case, ...fields }.
NodeType	Leaf | LeafList | NodeGroup | NodeGroupList | NodeChoice.
Appearance	Presentation options for a nodeGroup (flatten, noBorder).
CASE_KEY	The form-value key ('__case') that records a choice’s active case.

Inferred (advanced)

Type	Description
DFormGroup<G>	The FormGroup type inferred for a nodeGroup G.
DFormControl<N>	The control type inferred for a node N.
LeafRuntimeType<T>	Maps a leaf type string to its runtime value type.