Validation Class passing field name

CodeIgniter 4 Validation Library - eithRequest()

SEE: how it's handaling error messages.

I've scoured that page and I did not seeing anything on how to get the label to the Validation class.

But your direction gave me an idea which wasn't spelled out in the documents (some of us need real world examples beaten over our heads).

So here's the solution for anyone wanting it.

MyController.php

PHP Code:

$this->validation->setRules([
    'first_name' => [
        'label' => 'First Name',
        'rules' => 'myFieldCheck', 
        'errors' => [
            'myFieldCheck' => 'The {field} field needs to be last least 1 character long.'
        ]
    ],
]); 


MyValidationRules.php

PHP Code:

class MyValidationRules
{
    public function myFieldCheck(string $str, string &$error = null): bool
    {
        if(!strlen(trim($str)) > 0){
           return false;
       } else {
            return true;
        }
    }
} 


Thanks for the help!