# `Statifier.Effect.Send`
[🔗](https://github.com/riddler/statifier-ex/blob/v2.0.0/lib/statifier/effect/send.ex#L1)

Payload for `{:send, %__MODULE__{}}` - spec 6.2's `<send>`, fired
immediately (no `delay`/`delayexpr`; that variant is
`Statifier.Effect.SendDelayed`). Fields are the element's own attribute
names so the not-yet-implemented session/invoke support, which will give
this effect its semantics, can extend rather than rename them: `event` is
the event name being sent, `target` and `type` are the `target`/`type`
attributes (`nil` when the element omits them), `data` is the resolved
payload, `send_id` is the `id` attribute (generated when the element has
none).

`c_index` is the identity (`docs/observability.md` constraint 3) of the
`<send>` content node that produced this effect - never a compiled
content-node struct. `owner` names which block emitted the send (the same
gap `Statifier.Effect.Log`'s own moduledoc describes: `c_index` alone does
not say which `<onentry>`/`<onexit>` block or transition it belongs to).
`macrostep`/`microstep`/`round` are the step counters as they stand at the
moment of the send.

`id_from_author?` is `true` when the document wrote `id` or `idlocation`
on this `<send>`, `false` when `send_id` was generated. It exists for
C.1's empty-`sendid` rule: a delivered event's `sendid` must be `nil` when
the author never named the send, and `send_id` alone cannot express that
distinction, since ADR-0035 always mints one either way.

## `data` may carry `:undefined`, untranslated

`docs/adr/0037-unbound-spelled-undefined-at-the-writer.md`'s open question
1, answered: a `namelist` entry or `<param location>` referencing a
declared-but-unbound datamodel root reads `{:ok, :undefined}` off the
normalized context (`resolve_params/2` in
`Statifier.Machine.Content.Send`), and that atom lands in `data` exactly
as written - no translation at this boundary. An *undeclared* root is a
different case entirely: it is an argument failure that discards the
whole `<send>` (ADR-0036), never a value that reaches `data` at all. This
settles the `#_internal`, same-session, and `#_scxml_<sessionid>` routes
that exist today; a future external-wire processor (BasicHTTP or
otherwise) owns its own `:undefined` encoding at its own boundary, not
here.

# `owner`

```elixir
@type owner() :: Statifier.Machine.Content.owner()
```

Which block emitted the send - `Statifier.Machine.Content.owner/0`.

# `t`

```elixir
@type t() :: %Statifier.Effect.Send{
  c_index: non_neg_integer() | nil,
  data: term(),
  event: String.t(),
  id_from_author?: boolean(),
  macrostep: non_neg_integer(),
  microstep: non_neg_integer(),
  owner: owner() | nil,
  round: non_neg_integer(),
  send_id: String.t() | nil,
  target: String.t() | nil,
  type: String.t() | nil
}
```

---

*Consult [api-reference.md](api-reference.md) for complete listing*