Taking the reference of a method has bad error messages

[madsmtm]

Code

struct LlamaModel;

impl LlamaModel {
    fn chat_template(&self) -> Result<&str, ()> {
        todo!()
    }
}

fn template_from_str(_x: &str) {
    
}

fn main() {
    let model = LlamaModel;
    template_from_str(&model.chat_template);
}

Current output

Compiling playground v0.0.1 (/playground)
error[E0609]: no field `chat_template` on type `Model`
  --> src/main.rs:15:30
   |
15 |     template_from_str(&model.chat_template);
   |                              ^^^^^^^^^^^^^ unknown field

For more information about this error, try `rustc --explain E0609`.
error: could not compile `playground` (bin "playground") due to 1 previous error

Desired output

Compiling playground v0.0.1 (/playground)
error[E0615]: attempted to take value of method `chat_template` on type `Model`
  --> src/main.rs:11:11
   |
11 |     template_from_str(&model.chat_template);
   |                              ^^^^^^^^^^^^^ method, not a field
   |
help: use parentheses to call the method
   |
11 |     template_from_str(&model.chat_template());
   |                                           ++

For more information about this error, try `rustc --explain E0615`.
error: could not compile `playground` (bin "playground") due to 1 previous error

Rationale and extra context

A friend pointed this out while working with llama_cpp that they accidentally passed the reference to a method, instead of calling the method. It would be nice if the compiler could suggest to call the method instead of thinking that it is a missing field.

Rust Version

$ rustc --version --verbose
rustc 1.89.0 (29483883e 2025-08-04)
binary: rustc
commit-hash: 29483883eed69d5fb4db01964cdf2af4d86e9cb2
commit-date: 2025-08-04
host: aarch64-apple-darwin
release: 1.89.0
LLVM version: 20.1.7

Anything else?

No response

[chenyukang]

emm, if there is an unwrap, the error message will be as expected:

error[E0615]: attempted to take value of method `chat_template` on type `LlamaModel`
  --> ./t/method.rs:13:29
   |
13 |     template_from_str(model.chat_template.unwrap());
   |                             ^^^^^^^^^^^^^ method, not a field
   |
help: use parentheses to call the method
   |
13 |     template_from_str(model.chat_template().unwrap());
   |                                          ++