fn main() -> Result<(), Box<dyn std::error::Error>> {
    let s = std::fs::read_to_string(std::env::var("CARGO_MANIFEST_DIR")? + "/cargo.lock")?;
    let lock = s.parse::<toml::Value>().unwrap();
    let mut reqwest_ver: Option<String> = None;
    for p in lock.as_table().unwrap()["package"].as_array().unwrap() {
        if p["name"].as_str().unwrap() == "reqwest" {
            reqwest_ver = Some(p["version"].as_str().unwrap().into());
            break;
        }
    }
    println!(
        "cargo:rustc-env=REQWEST_VER={}",
        reqwest_ver.ok_or_else(|| "No reqwest ver found")?
    );
    Ok(())
}