Background

Let us quickly troubleshoot a rust build warning.

Error Message

Textual

>cargo build
warning: field `person_name` is never read
  --> src\main.rs:27:7
   |
25 | struct Congregant
   |        ---------- field in this struct
26 | {
27 |       person_name: String
   |       ^^^^^^^^^^^
   |
   = note: `Congregant` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
   = note: `#[warn(dead_code)]` on by default

Image

Source Code

Code Snippet

Here is a snippet of our source code

#[derive(Debug)]
struct Congregant 
{
      person_name: String
      
    , bible_translation: String
    
    , is_kjv: bool
    
    , err:String
    
}

Error Message Review

Textual

Explanation

Conpiler has this to say:-

1. = note: `Congregant` has a derived impl for the trait `Debug`, but this is intentionally ignored during dead code analysis
   • Yes, you have enabled the debug flag
   • But, I will intentionally ignore the Dubug trait while checking for “dead code”
2. = note: `#[warn(dead_code)]` on by default
   • #[warn(dead_code)]
     • Warning for dead ( unneeded ) code is on by default
     • In this case, we are setting the person’s name, yet never reading it

Remediation

Outline

1. Source Code
   • Added directives
     • #[allow(dead_code)]
     • #[allow(unused)]
   • Added implementation code for structure display

Source Code

Remediation

Code

impl std::fmt::Display for Congregant
{

	fn fmt
	(
		&self, f: &mut std::fmt::Formatter
	) -> std::fmt::Result 
	{
		
		let buffer:String;
		
		buffer = format!
			(
				  "{0}\r\n\tBible Translation:- {1}\r\n\tIs KJV:- {2}\r\n\tErr:- {3}\r\n"
				, self.person_name
				, self.bible_translation
				, self.is_kjv
				, self.err
			);
			
		let result =
					writeln!
					(
						  f
						, "{}"  
						, buffer
					);
					
		return result;
		
	}

	
}

Online Code IDE

OnlineGDB

1. RustKJVOnly
   Link

Source Code Control

GitLab

1. Rust – Exception Handling
   • Link
     Link
   • Files
     • 01) RustKJVOnly.rs

Listening

Listenting to who I need to listen to:-

Dedication