Enum Change 

pub enum Change<'g> {
    Add(Node<'g>),
    Remove(Node<'g>),
    Edit {
        node: Node<'g>,
        old: Node<'g>,
    },
    Child {
        node: Node<'g>,
        rel: RelId,
        child: Box<Change<'g>>,
    },
}

A downstream incremental change. Mirrors zql/src/ivm/change.ts but as a real tagged union (the JS uses a tuple where slot 2 aliases OLD_NODE / CHILD_DATA — the enum removes that aliasing footgun).

Variants

Add(Node<'g>)

Remove(Node<'g>)

Edit

An in-place edit: the row’s PK is unchanged but some columns differ. Holds both the new node and the old node (makeEditChange — change.ts). A connection with split-edit keys never sees this (the source decomposes it into Remove(old)+Add(new) before fan-out, §3.6); it survives only for connections that don’t split.

Fields

node: Node<'g>

old: Node<'g>

Child

Fields

node: Node<'g>

rel: RelId

The relationship slot the child change belongs to (index, not a name — foundations §3.4). The View resolves it to a name via the schema.

child: Box<Change<'g>>

Implementations

impl<'g> Change<'g>

pub fn change_type(&self) -> ChangeType

This change’s ChangeType discriminant (payload-free).

pub fn primary_row(&self) -> &Row

The row identifying this change’s node (the new row for an Edit; the changed-child’s row for a Child). On a child-side join push this is the row whose join key selects the matching parents (join.ts#pushChildChange).