Result and the question mark operator in Rust

Rust

? propagates the error to the caller, which is why Rust functions rarely need explicit error branches.

use std::fs;

fn read_config(path: &str) -> Result<Config, Box<dyn std::error::Error>> {
    let text = fs::read_to_string(path)?;
    let config: Config = toml::from_str(&text)?;
    Ok(config)
}

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Systems rust errors result chris

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