694c06f3d0
# Objective Currently the `missing_docs` lint is allowed-by-default and enabled at crate level when their documentations is complete (see #3492). This PR proposes to inverse this logic by making `missing_docs` warn-by-default and mark crates with imcomplete docs allowed. ## Solution Makes `missing_docs` warn at workspace level and allowed at crate level when the docs is imcomplete.
48 lines
1.2 KiB
Rust
48 lines
1.2 KiB
Rust
//! This example creates a custom [`SystemParam`] struct that counts the number of players.
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use bevy::{ecs::system::SystemParam, prelude::*};
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fn main() {
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App::new()
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.insert_resource(PlayerCount(0))
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.add_systems(Startup, spawn)
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.add_systems(Update, count_players)
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.run();
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}
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#[derive(Component)]
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struct Player;
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#[derive(Resource)]
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struct PlayerCount(usize);
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/// The [`SystemParam`] struct can contain any types that can also be included in a
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/// system function signature.
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///
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/// In this example, it includes a query and a mutable resource.
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#[derive(SystemParam)]
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struct PlayerCounter<'w, 's> {
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players: Query<'w, 's, &'static Player>,
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count: ResMut<'w, PlayerCount>,
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}
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impl<'w, 's> PlayerCounter<'w, 's> {
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fn count(&mut self) {
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self.count.0 = self.players.iter().len();
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}
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}
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/// Spawn some players to count
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fn spawn(mut commands: Commands) {
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commands.spawn(Player);
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commands.spawn(Player);
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commands.spawn(Player);
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}
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/// The [`SystemParam`] can be used directly in a system argument.
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fn count_players(mut counter: PlayerCounter) {
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counter.count();
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println!("{} players in the game", counter.count.0);
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}
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