# `CaravelaSvelte.Renderer`
[🔗](https://github.com/rsousacode/caravela_svelte/blob/v0.1.0/lib/caravela_svelte/renderer.ex#L1)

Behaviour for Svelte render backends.

A renderer knows how to turn raw component assigns (name, props,
slots, options) into a *prepared* assigns map that downstream code
— usually the `CaravelaSvelte.svelte/1` function component — uses
to emit the final output.

The seam exists so `CaravelaSvelte.Rest` (Phase B.2) can reuse the
same SSR pipeline and client-payload packaging, but emit a
Plug.Conn response instead of HEEx.

Today the only implementation is `CaravelaSvelte.Live`, which
preserves the behaviour `live_svelte` has always had.

## Prepared assigns shape

The prepared assigns map MUST include every key the
`CaravelaSvelte.svelte/1` template reads:

  * `:init` — true on first render / dead render
  * `:slots` — decoded slot map
  * `:ssr_render` — result of SSR (or nil when disabled)
  * `:svelte_id` — stable DOM id
  * `:props_to_send` — map that will be JSON-encoded onto `data-props`
  * `:use_diff` — boolean flag
  * `:props_diff` — compressed JSON-patch ops list
  * `:streams_diff` — compressed stream patch ops list

Plus whatever the original assigns carried (name, class, etc.).

## Configuration

The default renderer is `CaravelaSvelte.Live`. Override per-app:

    config :caravela_svelte, :renderer, MyApp.CustomRenderer

# `assigns`

```elixir
@type assigns() :: map()
```

# `prepared`

```elixir
@type prepared() :: map()
```

# `prepare`

```elixir
@callback prepare(assigns()) :: prepared()
```

Prepare component assigns for rendering. See the moduledoc for
the required output shape.

# `configured`

```elixir
@spec configured() :: module()
```

Returns the configured renderer module. Defaults to `CaravelaSvelte.Live`.

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