no method named map_err found for enum Option in the current scope

[sgtnasty]

I cant seem to find any solutions to this online, but it appears map_err does not exist for Option. Do I need to create a method for it? I am confused at this point how to approach.

Here is the code:

 fn explains_why_generating_nametag_text_fails() { assert_eq!( generate_nametag_text(String::new()) .as_ref() .map_err(|e| e.as_str()), Err("Empty names aren't allowed"), ); }

Errors show as:

error[E0599]: no method named `map_err` found for enum `Option` in the current scope --> exercises/13_error_handling/errors1.rs:37:18 | 35 | / generate_nametag_text(String::new()) 36 | | .as_ref() 37 | | .map_err(|e| e.as_str()), | |_________________-^^^^^^^ | help: there is a method `map_or` with a similar name, but with different arguments --> /home/ronaldo/.rustup/toolchains/stable-x86_64-unknown-linux-gnu/lib/rustlib/src/rust/library/core/src/option.rs:1159:5 | 1159 | / pub fn map_or<U, F>(self, default: U, f: F) -> U 1160 | | where 1161 | | F: FnOnce(T) -> U, | |__________________________^ 

[sgtnasty]

I just needed to re-read the header of the exercise and I figured out I needed to change the Option to a Result.