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# Objective Provide a starting point for #3951, or a partial solution. Providing a few comment blocks to discuss, and hopefully find better one in the process. ## Solution Since I am pretty new to pretty much anything in this context, I figured I'd just start with a draft for some file level doc blocks. For some of them I found more relevant details (or at least things I considered interessting), for some others there is less. ## Changelog - Moved some existing comments from main() functions in the 2d examples to the file header level - Wrote some more comment blocks for most other 2d examples TODO: - [x] 2d/sprite_sheet, wasnt able to come up with something good yet - [x] all other example groups... Also: Please let me know if the commit style is okay, or to verbose. I could certainly squash these things, or add more details if needed. I also hope its okay to raise this PR this early, with just a few files changed. Took me long enough and I dont wanted to let it go to waste because I lost motivation to do the whole thing. Additionally I am somewhat uncertain over the style and contents of the commets. So let me know what you thing please.
30 lines
988 B
Rust
30 lines
988 B
Rust
//! Illustrates how to make a single system from multiple functions running in sequence and sharing
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//! their inputs and outputs.
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use anyhow::Result;
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use bevy::prelude::*;
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fn main() {
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App::new()
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.insert_resource(Message("42".to_string()))
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.add_system(parse_message_system.chain(handler_system))
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.run();
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}
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#[derive(Deref)]
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struct Message(String);
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// this system produces a Result<usize> output by trying to parse the Message resource
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fn parse_message_system(message: Res<Message>) -> Result<usize> {
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Ok(message.parse::<usize>()?)
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}
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// This system takes a Result<usize> input and either prints the parsed value or the error message
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// Try changing the Message resource to something that isn't an integer. You should see the error
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// message printed.
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fn handler_system(In(result): In<Result<usize>>) {
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match result {
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Ok(value) => println!("parsed message: {}", value),
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Err(err) => println!("encountered an error: {:?}", err),
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}
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}
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