Function `request_value`

fn request_value<'a, T, impl Error + ?Sized: Error + ?Sized>(err: &'a impl Error + ?Sized) -> Option<T>
where
    T: 'static

Requests a value of type T from the given impl Error.

Examples

Get a string value from an error.

#![feature(error_generic_member_access)]
use std::error::Error;
use core::error::request_value;

fn get_string(err: &impl Error) -> String {
    request_value::<String>(err).unwrap()
}