candy-rs

Syntaxic sugar for Rust: macros for lighter error handling code, and more.

Examples

``rust //! Run withcargo run --example do_loop -- `

[macro_use] extern crate candy;

use ::std::*;

type ErrorMsg = borrow::Cow<'static, str>;

fallible! { fn main () -> () =>! ErrorMsg : let inputnumber: u64 = { let (mbargv0, mbargv1) = { let mut args = env::args(); (args.next(), args.next()) }; let progname = mbargv0.unwrap(); match mbargv1 .andthen(|argv1| argv1.parse().ok()) { Some(number) => number, _ => throw!(format!("Usage: {} ", progname)), } }; collatzconjecture(inputnumber); }

fn collatzconjecture (mut n: u64) { doloop!({ println!("n = {}", n); if n % 2 == 0 { n /= 2; } else { n = 3 * n + 1; }; } while n != 1); println!("Did reach 1."); } ```

``rust //! Run withcargo run --example catch`

[macro_use] extern crate candy;

use ::std::{ *, io::Write, };

fn main () { debugprintall([0b101010, 0x45].iter()) }

fn debugprintall ( iterable: impl IntoIterator, ) { let to_stdout = &mut io::stdout();

// `catch!` allows using the `?` operator. Isn't that nice?
match catch!({
    write!(to_stdout, "[")?;
    let mut iterator = iterable.into_iter();
    let mut count = 0;
    if let Some(first) = iterator.next() {
        count += 1;
        write!(to_stdout, "{:?}", first)?;
        while let Some(next) = iterator.next() {
            count += 1;
            write!(to_stdout, ", {:?}", next)?;
        };
    };
    write!(to_stdout, "]\n")?;
    count
} -> usize =>! io::Error)
{
    Err(io_err) => {
        eprintln!(
            "{:?} : could not write to stdout!? Oh well, who cares?",
            io_err,
        );
    },
    Ok(n) => {
        eprintln!("Successfully wrote {} elements to stdout", n);
    },
}

} ```

Usage

• Add this line to your Cargo.toml (under [dependencies]): toml candy = "0.1.5"

• Add this to your .rs code: ```rust

  [macro_use] extern crate candy;

  ```