Macro ios_app 

macro_rules! ios_app {
    ($state_ty:ty, $build:expr $(,)?) => { ... };
    ($state_ty:ty, $state_init:expr, $build:expr $(,)?) => { ... };
}

Bind a generated app’s State/build to the fixed iOS C-ABI exports (Makepad app_main! precedent).

Stamps out the twenty-four frust_* symbols the generated Swift app declares (the seven lifecycle/input exports, the three text-input exports — frust_ime_apply, frust_ime_state_json, frust_string_free — the four clipboard/system-edit-menu exports — frust_edit_command, frust_take_clipboard_write, frust_take_paste_request and frust_selection_toolbar_json, the route that keeps every paste exempt from iOS’s paste-permission alert by going through the platform’s own menu (see ffi_glue::edit_command) — frust_set_appearance (the dark-mode export), frust_set_reduce_motion (the reduced-motion accessibility export — the same transport over a different sensor: UIAccessibility, not UITraitCollection), frust_on_deep_link (cold-start/running deep-link delivery), frust_init_accessibility (the accesskit adapter attach — the one export whose UIView pointer the CAMetalLayer-only frust_init cannot supply), frust_set_insets (the SafeArea inset delivery), frust_system_ui_state (the system-UI override peek — see ffi_glue::system_ui_state), plus frust_set_surface_mode and frust_platform_view_commands_json (the translucent-surface opt-in latch and command-backlog peek getter — see ffi_glue::set_surface_mode/ffi_glue::platform_view_commands_json), plus frust_set_present_sync and frust_present_frame (the present-sync latch and its per-tick UI-thread present — see ffi_glue::set_present_sync/ffi_glue::present_frame)), each delegating to the non-generic runtime in [ffi_glue]. frust_init constructs the app’s erased view tree and returns an opaque handle; the rest operate on that handle. It also initializes the process-wide [frust_reactive::ReactiveRuntime] (idempotent, framework-side inside [ffi_glue::init] rather than emitted here, so both arms below get it with no macro duplication) before the state/view tree is constructed.

Unlike android_app!, this macro is call-site transparent: it is invoked unconditionally in the generated src/lib.rs, because every symbol it emits is itself #[cfg(target_os = "ios")], so off-iOS the invocation expands to nothing:

frust::ios_app!(AppState, move |s| root.build(s));

Two forms:

• ios_app!($state_ty, $build) — $state_ty must implement Default; the initial state is $state_ty::default().
• ios_app!($state_ty, $state_init, $build) — $state_init is a FnOnce() -> $state_ty factory, for a state type that doesn’t implement Default (e.g. one a future Component::init builds). The 2-arg form delegates to this one with <$state_ty as Default>::default as the factory.

$build is the root component’s build closure, a FnMut(&mut State) -> impl View<State> (move |s| root.build(s)).