Rust Base64 Conversion Stuff

base64.rs

extern crate rustc_serialize;

use rustc_serialize::base64::{self, ToBase64, FromBase64};

#[derive(Clone, Eq, PartialEq)]
pub enum Base64 {
    Standard(String),
    UrlSafe(String),
    Mime(String),
}

macro_rules! implement_to {
    ($name:ident, $variant_type:expr, $variant_pat:pat) => (
        fn $name(&self) -> Result<Base64, Error> {
            match *self {
                Base64::Standard(ref base64) | Base64::UrlSafe(ref base64) | Base64::Mime(ref base64) => {
                    let decoded = str::from_base64(base64)?;
                    let encoded = decoded.to_base64()?;
                    Ok($variant_type(encoded))
                }
            }
        }
    )
}

impl Base64 {
    fn config(&self) -> base64::Config {
        use Base64::*;

        match *self {
            Standard(_) => base64::STANDARD,
            UrlSafe(_) => base64::URL_SAFE,
            Mime(_) => base64::MIME,
        }
    }

    implement_to!(to_standard, Base64::Standard, Base64::Standard(_));
    implement_to!(to_url_safe, Base64::UrlSafe, Base64::UrlSafe(_));
    implement_to!(to_mime, Base64::Mime, Base64::Mime(_));
}