Macro ios_main 

macro_rules! ios_main {
    ($root:expr) => { ... };
    ($title:expr, $root:expr) => { ... };
}

Expands to the day_main C export the iOS Runner’s main.swift calls (@_silgen_name("day_main")). The optional title is currently unused on iOS (the window fills the screen bounds); accepted for future window-scene use.

day::ios_main!(root);              // or: day::ios_main!("My App", root);