tiny-error 1.0.0

//! A tiny crate for error handling. It is able to convert items of the 
//! [`Error`](https://doc.rust-lang.org/std/error/trait.Error.html) trait into
//! their messages, allowing for easy propagation. 
//!
//! # Examples
//! 
//! ```rust
//! use tiny_error::ErrorMessage;
//! 
//! use std::{
//!     env,
//!     fs,
//!     path::PathBuf,
//! };
//! 
//! fn main() -> Result<(), ErrorMessage> {
//!     // Text when failed:
//!     // Error: Invalid input
//!     // Correct Usage: `[crate_name] example/file/path.txt`
//!     let path = get_path()?;
//!     // Text when failed: 
//!     // Error: No such file or directory (os error 2)
//!     let file = fs::read_to_string(path)?;
//! 
//!     Ok(())
//! }
//! 
//! // Gets the first argument passed. If none or more were, returns an
//! // `ErrorMessage`.
//! fn get_path() -> Result<PathBuf, ErrorMessage> {
//!     let mut args = env::args().skip(1);
//!     let arg = args.next().filter(|_| args.next().is_none());    
//! 
//!     arg
//!         .map(|input| input.into())
//!         .ok_or_else(|| ErrorMessage::new(
//!             "Invalid input\n\
//!              Correct Usage: `[crate_name] example/file/path.txt`"
//!         ))
//! }
//! ```

use std::{
    error::Error,
    fmt::{Debug, Formatter, Result as FmtResult},
};

/// The struct that holds the error message.
pub struct ErrorMessage(String);

impl ErrorMessage {
    /// Constructs a new [`ErrorMessage`] with the passed parameter,
    /// converting it into a [`String`](https://doc.rust-lang.org/std/string/struct.String.html).
    pub fn new<S: Into<String>>(message: S) -> Self {
        ErrorMessage(message.into())
    }
}

impl Debug for ErrorMessage {
    fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
        write!(f, "{}", self.0)
    }
}

impl<E: Error> From<E> for ErrorMessage {
    fn from(value: E) -> Self {
        ErrorMessage(format!("{}", value))
    }
}