Crate 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.

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」

Derive Macros

• Code