Crate utils_results

First, You should make your own an error set.

Example

err! {
     BrokenHeader => "broken header."
     AnotherHeader => "not matched header."
     FileNotFound => "file not found."
     EmptyArgument => "empty argument."
     UnexpectedEof => "unexpected eof."
     OutOfBounds => "index out of bounds."
     NotMatched => "btw not matched."
}

And just errbang!

errbang!(err::BrokenHeader);

More Examples

fn foo() -> Result<bool> { // Our Master Result Type
    let bar = 2;
    match bar {
        0 => Ok(true),
        1 => Ok(false),
        _ => errbang!(err::NotMatched, "{} is {}", "bar", bar),
    }
}
fn main() -> Result<()> {
    let _is_bar_zero = foo()?;
    Ok(())
}

errbang!("error.");
errbang!(err::MyError1);
errbang!(err::MyError2, "cannot find.");
errbang!(err::MyError3, "{} is {}", "bar", 2);

| Result

[src/main.rs 40:1] unexpected eof. bar is 2 <err::UnexpectedEof>

unwrapping error input data. also can easily compare them.

fn foo() -> Result<()> {
    // example
    return errbang!(err::Bar, "this is input.");
}

assert_eq!(
   errunwrap!(foo(), err::Bar), "this is input."
);

Important

• 1. One result type(anyhow).
• 2. All casted errors have their own chaining error’ information(all the previous errors).

if you follow below rules, you can easily debug all your projects.

errbang -> errcast -> errcast -> … -> errcast -> errextract

---

Quick Overview

use utils_results::*;

err! {
    One => "this error is first one."
    Two => "this error is second one."
    Three => "this error is third one."
    Well => "is this?"
}


fn aaa() -> Result<usize> {
    return errbang!(err::One, "{}.error bang!", 1);
}

fn bbb() -> Result<usize> {
    let n = errcast!(aaa(), err::Two, "{}.two <- one.", 2);
    Ok(n)
}

fn ccc() -> Result<usize> {
    Ok(errcast!(bbb(), err::Three, "{}.three <- two.", n))
}


fn main() -> Result<()> {
    let c = errextract!(ccc(), err::Well => 127);
    eprintln!("1/{} is cosmological constant.", c);
    Ok(())
}

| Result

Error:
[src/main.rs 11:12] this error is first one. 1.error bang! <err::One> aaa()
                    ⎺↴
[src/main.rs 14:13] this error is second one. 2.two <- one. <err::Two> bbb()
                    ⎺↴
[src/main.rs 18:8] this error is third one. 3.three <- two. <err::Three>

If the matching error be changed,

// Well to Three
let c = errextract!(ccc(), err::Three => 127);

| Result

1/127 is cosmological constant.

---

errcast

Any type of error can be converted into our Master Error.

// example
// <Unwraped Ok> = errcast!(<Any Result>, <Master Err>, <Optional,..>);
let num_read = errcast!(file.read(&mut buf), err::ReadErr, "this is {} data.", "meta");

---

Simply just do this!

let file = errcast!(File::open("test"), err::FileOpenError)

or…

// Master `Result` can take any errors
let file = File::open("test")?;

// if cfg!(no_std),
let file = io_to_err!(File::open("test"))?;

But, errcast -> errextract combo is always good choice.

fn exe(path: &str) -> Result<usize> {
    let file = errcast!(File::open("test"), err::FileOpenError);
    // .....
    // ...
    Ok(num)
}

fn main() -> Result<()> {
    /// non panic unwraping
    /// and specific error can return
    /// matching block
    let num = errextract!(exe(path),
        err::FileOpenError => 0);
    /// other errors will go out -> Result<T>

    Ok(())
}

---

Master Result

• Please use our Master Result<T> instead std::result::Result or io::Result etc..
• this is anyhow Result.
  

---

utils-results/lib.rs Definition

/// Master Result
pub type Result<T> = anyhow::Result<T>;

---

just put this in your project.

pub use utils_results::*;

You can also convert any type of Result

// to our Master Result
resultcast!(handle.join().unwrap())?;

Macros

err

create custom error list

err_to_io

casting Master Error to core::io Error matched by io_err

errbang

make some error. floating Err(..)

errcast

Any type of error can be converted into our Master Error. (non panic unwraping)

errcast_panic

Any type of error can be converted into our Master Error. (and unwraping)
And then panic!

errextract

non panic unwraping and specific error can return matching block
other errors will go out -> Result<T>

errmatch

any type of inside Err() can match this

errpanic

panic! with Master Error

errprint

println! with Master Error

errunwrap

unwrapping error input data.

io_err

matching io::Error and Master Error to use casting error macros

io_to_err

casting core::io Error to Master Error matched by io_err

resultcast

this will convert any result type to Master Result.

Structs

Error

Master Result The Error type, a wrapper around a dynamic error type.

Type Aliases

Result

Master Result Result<T, Error>