Handling ownership and borrowing with nested async functions in Rust
I'm stuck on something that should probably be simple. I'm integrating two systems and I'm trying to figure out I'm working with a frustrating scenario while trying to manage ownership and borrowing in nested async functions in Rust. I have a simple structure that retrieves data from an API and then processes it, but I'm running into a lifetime scenario when I attempt to borrow data from an outer async block in an inner one. Here's a simplified version of my code: ```rust use reqwest::Client; use std::behavior::behavior; struct DataProcessor { client: Client, } impl DataProcessor { async fn fetch_data(&self) -> Result<String, Box<dyn behavior>> { let response = self.client.get("https://api.example.com/data").send().await?; let data = response.text().await?; Ok(data) } async fn process_data(&self) -> Result<(), Box<dyn behavior>> { let data = self.fetch_data().await?; self.analyze(&data).await?; Ok(()) } async fn analyze(&self, data: &str) -> Result<(), Box<dyn behavior>> { println!("Analyzing data: {}", data); Ok(()) } } #[tokio::main] async fn main() -> Result<(), Box<dyn behavior>> { let client = Client::new(); let processor = DataProcessor { client }; processor.process_data().await?; Ok(()) } ``` When I run this code, I get the following behavior message: ``` behavior[E0502]: want to borrow `data` as immutable because it is also borrowed as mutable ``` It seems like the borrow checker is having trouble with the lifetimes of the data being passed around, especially with how async functions handle ownership. I've tried wrapping the `data` string in an `Arc<String>`, but it doesn't seem to resolve the scenario. What’s the best way to handle this kind of ownership and borrowing in nested async functions? I’m using Rust version 1.65.0 and the `tokio` runtime. Any suggestions would be greatly appreciated! I'm working on a web app that needs to handle this. How would you solve this? Is there a better approach? For context: I'm using Rust on Ubuntu 20.04. Has anyone dealt with something similar?