route.placeholder_type: Placeholder is not typed with a named scalar or an X.id

Placeholder is not typed with a named scalar or an X.id.

Area 7, HTTP; not declinable; the next step is usually the agent's.

A placeholder is typed with a named scalar or an X.id, never optional:

example

type Memo = Text {    max_length: 200}type MemoId = Uuid {}type AddMemo = Input {    text: Memo}type MemoView = Output {    text: Memo}action add_memo(input: AddMemo) -> MemoView {    return MemoView {        text: input.text    }}action tag_memo(memo_id: MemoId, input: AddMemo) -> MemoView {    return MemoView {        text: input.text    }}routes Memos {    prefix: /memos    POST /{memo_id: MemoId?} {        input: AddMemo        output: MemoView        run: tag_memo(memo_id, input)    }}

text

error: `memo_id` can't be typed `MemoId?` --> main.jadpo:30:21   |30 |     POST /{memo_id: MemoId?} {   |                     ^^^^^^^ not a named scalar  reason: A placeholder's type is a named scalar or an `X.id`: a placeholder is always there, so it is never optional.  next: Type it with a named type built on a scalar, or an `X.id` (agent)  rule: route.placeholder_type  help: https://jadpo.dev/docs/errors/route.placeholder_typecheck failed: 1 error, 1 file

A placeholder typed with a field its type doesn't declare is type.unknown_field at its type, as any field type is:

example

type NoteText = Text {    max_length: 200}type NoteView = Output {    text: NoteText}entity Note {    id: Uuid    text: NoteText    policy: {        read: [Access.public]    }}query find_note(note_id: Note.id) fails NoteNotFound -> NoteView {    from: Note    where: Note.id == note_id    missing: NoteNotFound}routes Notes {    prefix: /notes    GET /{note_id: Note.ident} {        authentication: RouteAuthentication.none        output: NoteView        run: find_note(note_id)    }}

text

error: `Note` has no field `ident` --> main.jadpo:27:20   |27 |     GET /{note_id: Note.ident} {   |                    ^^^^^^^^^^ not declared  reason: A field type is written `Type.field`, naming a field the type declares.  next: Name a field of `Note` (agent)  rule: type.unknown_field  help: https://jadpo.dev/docs/errors/type.unknown_fieldcheck failed: 1 error, 1 file