Enhance Rust errors with file and line details
Errors are for the regular case when the program detected that  something wasn&#x27;t allowed or set up right and the program did everything right (by returning an error). Why then do you need the rs source code file&amp;line of the place where everything went right? What about all the other places where everything went right? Wanna log those, too? :)<p>What will the end user do with rs source code file&amp;line?<p>I read the example on the page. What they want to do is return which argument of `add` the error was with. Well, then introduce an `AddError` (or I guess it could be a more generic `BinaryOperationError`) like this: `struct AddError { argument_1: Option&lt;...&gt;, argument_2: Option&lt;...&gt; }` and return that error from `add`. Then you can even have it return errors due to both arguments at the same time.<p>One use case of the crate would be if you made a mistake and something actually shouldn&#x27;t be an error but should be a panic, and you wanna find where it is in order to change it to a panic. So, debugging.