Struct Systems 

#[non_exhaustive]
pub struct Systems {
    pub state: Option<(State, Box<dyn Fn(&mut World, State, State)>)>,
    pub start: Vec<Box<dyn FnOnce(&mut World)>>,
    pub update: Vec<Box<dyn Fn(&mut World)>>,
    pub keyboard: Vec<Box<dyn Fn(&mut World, KeyCode, bool)>>,
    pub mouse_position: Vec<Box<dyn Fn(&mut World, PhysicalPosition<f64>)>>,
    pub mouse_button: Vec<Box<dyn Fn(&mut World, MouseButton, bool)>>,
    pub mouse_wheel: Vec<Box<dyn Fn(&mut World, f32, f32)>>,
    pub event: Vec<Box<dyn Fn(&mut World, WindowEvent)>>,
}

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

state: Option<(State, Box<dyn Fn(&mut World, State, State)>)>

start: Vec<Box<dyn FnOnce(&mut World)>>

update: Vec<Box<dyn Fn(&mut World)>>

keyboard: Vec<Box<dyn Fn(&mut World, KeyCode, bool)>>

mouse_position: Vec<Box<dyn Fn(&mut World, PhysicalPosition<f64>)>>

mouse_button: Vec<Box<dyn Fn(&mut World, MouseButton, bool)>>

mouse_wheel: Vec<Box<dyn Fn(&mut World, f32, f32)>>

event: Vec<Box<dyn Fn(&mut World, WindowEvent)>>

Implementations

impl Systems

pub fn new() -> Self