#error #enums #error-handling #derive #macro-derive

macro enum-code

derive(Code) simplifies error handling by providing an easy-to-use enumeration of error codes

2 releases

0.1.1 Jun 14, 2023
0.1.0 Jun 14, 2023

#2877 in Rust patterns

MIT license

7KB
58 lines

enum-code

Introduction

enum-code is a derive macro for enum types. This library generates code that associates error codes with error types. It can be used in conjunction with the thiserror crate. Developers can quickly retrieve error codes by calling the get_code method.

Installation

enum-code is published on Cargo and can be installed using:

$ cargo add enum-code

Usage

  1. Add the Code attribute to the enum type:

    #[derive(enum_code::Code)]
    enum TestError {
        #[code(1)]
        Tuple(String),
        #[code(2)]
        Struct { message: String },
        #[code(3)]
        Simple,
    }
    
  2. Code Generation

    For the TestError enum above, an associated impl TestError struct is generated, which includes a get_code method that returns the corresponding error code based on the variant value.

    impl TestError {
        pub const fn get_code(&self) -> u32 {
            match self {
                TestError::Tuple(..) => 1u32,
                TestError::Struct { .. } => 2u32,
                TestError::Simple => 3u32,
            }
        }
    }
    
  3. Retrieving Error Codes

    Error codes can be retrieved by calling get_code:

    let err = TestError::Tuple("error message".to_owned());
    let code = err.get_code();
    println!("error code: {}", code); // should print 「error code: 1」
    

LICENSE

MIT

Dependencies

~245–700KB
~17K SLoC