# fromWindow

Provides Navigation by adapting a browser Window's History API and `popstate` events.

## Signatures

```ts
export declare const fromWindow: (window?: Window) => Layer.Layer<Navigation, NavigationError, Uuid7State>;
```

## Why

Browser history remains the platform authority while Typed adds reactive entries, stable keys,
scoped handlers, and typed failures. Existing or foreign history state is reconciled instead of
assuming every entry was created by Typed.

## Ownership and lifetime

Layer acquisition reads and normalizes current history, allocates entry identity through `Uuid7State`,
and installs the `popstate` listener. The Layer Scope owns that listener, pending traversals,
reactive state, and handler registrations. Browser calls, malformed URLs, and unknown traversal
state fail as `NavigationError`; interruption runs Effect finalizers but cannot undo a platform
history mutation that already completed.

## Examples

```ts
import { fromWindow } from "@typed/navigation/fromWindow"

const NavigationLive = fromWindow(window)
```

Browser and server providers expose the same Navigation contract; server code should use
`@typed/navigation/memory` and must not evaluate the default `globalThis.window` argument.