Casts & Types — AQL

Computed field types

The type of a computed shape field is resolved in this order:

1. Explicit cast — a <Type> annotation always wins.
2. Inferred — a plain path is typed by resolving it through the schema: a path ending on a property takes that property’s type; one ending on a link takes its FK type (uuid).
3. any — anything else (a coalesce, function call, arithmetic, or a path that can’t be resolved to a scalar) is typed as any (json), and codegen prints a warning suggesting a cast.

So the common case needs no annotation:

multi select Application {
  *,
  owner := .project.organization.owner.id,    # inferred uuid
  iid   := .installation.installation_id      # inferred int64
}

A <Type> cast may be appended to any operand — a path (.a.b<uuid>), a parenthesized expression ((.name ?? .email)<str>), a subquery projection ((select …).slug<str>), or a bare literal ('{}'<json>). It uses the same type names as parameter annotations, emits (<expr>)::TYPE, and overrides inference / gives a type to an otherwise-uninferable field:

secrets := '{}'<json>           # a JSON literal default
who     := (.name ?? .email)<str>   # otherwise: warning + typed as any

An invalid path (a step that resolves to no property or link) is a compile error, not a warning.