tiny_error/
lib.rs

1//! A tiny crate for error handling. It is able to convert items of the 
2//! [`Error`](https://doc.rust-lang.org/std/error/trait.Error.html) trait into
3//! their messages, allowing for easy propagation. 
4//!
5//! # Examples
6//! 
7//! ```rust
8//! use tiny_error::ErrorMessage;
9//! 
10//! use std::{
11//!     env,
12//!     fs,
13//!     path::PathBuf,
14//! };
15//! 
16//! fn main() -> Result<(), ErrorMessage> {
17//!     // Text when failed:
18//!     // Error: Invalid input
19//!     // Correct Usage: `[crate_name] example/file/path.txt`
20//!     let path = get_path()?;
21//!     // Text when failed: 
22//!     // Error: No such file or directory (os error 2)
23//!     let file = fs::read_to_string(path)?;
24//! 
25//!     Ok(())
26//! }
27//! 
28//! // Gets the first argument passed. If none or more were, returns an
29//! // `ErrorMessage`.
30//! fn get_path() -> Result<PathBuf, ErrorMessage> {
31//!     let mut args = env::args().skip(1);
32//!     let arg = args.next().filter(|_| args.next().is_none());    
33//! 
34//!     arg
35//!         .map(|input| input.into())
36//!         .ok_or_else(|| ErrorMessage::new(
37//!             "Invalid input\n\
38//!              Correct Usage: `[crate_name] example/file/path.txt`"
39//!         ))
40//! }
41//! ```
42
43use std::{
44    error::Error,
45    fmt::{Debug, Formatter, Result as FmtResult},
46};
47
48/// The struct that holds the error message.
49pub struct ErrorMessage(String);
50
51impl ErrorMessage {
52    /// Constructs a new [`ErrorMessage`] with the passed parameter,
53    /// converting it into a [`String`](https://doc.rust-lang.org/std/string/struct.String.html).
54    pub fn new<S: Into<String>>(message: S) -> Self {
55        ErrorMessage(message.into())
56    }
57}
58
59impl Debug for ErrorMessage {
60    fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
61        write!(f, "{}", self.0)
62    }
63}
64
65impl<E: Error> From<E> for ErrorMessage {
66    fn from(value: E) -> Self {
67        ErrorMessage(format!("{}", value))
68    }
69}
tiny_error/lib.rs

tiny_error/
lib.rs
