Enum show_notes::e021::EmailEnum

pub enum EmailEnum {
    Address(String),
}

A "newtype" built by wrapping a String in a single-variant enum.

It's simple to use to create a wrapped variant, and then because it is a single-variant enum, we can also destructure it:

let email = EmailEnum::Address("[email protected]".into());
let EmailEnum::Address(just_the_string) = email;
send(just_the_string);

Note, however, that it is much more verbose.

Variants

Address(String)

Methods from Deref<Target = String>

pub fn as_str(&self) -> &str

Extracts a string slice containing the entire String.

Examples

Basic usage:

let s = String::from("foo");

assert_eq!("foo", s.as_str());

pub fn capacity(&self) -> usize

Returns this String's capacity, in bytes.

Examples

Basic usage:

let s = String::with_capacity(10);

assert!(s.capacity() >= 10);

pub fn as_bytes(&self) -> &[u8]

Returns a byte slice of this String's contents.

The inverse of this method is from_utf8.

Examples

Basic usage:

let s = String::from("hello");

assert_eq!(&[104, 101, 108, 108, 111], s.as_bytes());

pub fn len(&self) -> usize

Returns the length of this String, in bytes.

Examples

Basic usage:

let a = String::from("foo");

assert_eq!(a.len(), 3);

pub fn is_empty(&self) -> bool

Returns true if this String has a length of zero, and false otherwise.

Examples

Basic usage:

let mut v = String::new();
assert!(v.is_empty());

v.push('a');
assert!(!v.is_empty());

Trait Implementations

impl Deref for EmailEnum

type Target = String

The resulting type after dereferencing.

fn deref(&self) -> &String

Dereferences the value.