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use error::{Error, Result};
const MAX_MEMO_TEXT_LEN: usize = 28;
/// Memo attached to transactions.
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum Memo {
/// No memo
None,
/// Text Memo
Text(String),
/// Id Memo
Id(u64),
/// Hash Memo
Hash([u8; 32]),
/// Return Memo
Return([u8; 32]),
}
impl Memo {
/// Create new empty memo.
pub fn none() -> Memo {
Memo::None
}
/// Create new id memo.
pub fn id(id: u64) -> Memo {
Memo::Id(id)
}
/// Create new text memo. `text` must be shorter than 28 bytes.
pub fn text<S: Into<String>>(text: S) -> Result<Memo> {
let text = text.into();
if text.len() > MAX_MEMO_TEXT_LEN {
Err(Error::InvalidMemoText)
} else {
Ok(Memo::Text(text))
}
}
/// Create new hash memo.
pub fn hash(h: [u8; 32]) -> Memo {
Memo::Hash(h)
}
/// Create new return memo.
pub fn return_(r: [u8; 32]) -> Memo {
Memo::Return(r)
}
/// Return `true` if memo is `None`.
pub fn is_none(&self) -> bool {
match *self {
Memo::None => true,
_ => false,
}
}
/// Return `true` if memo is `Id`.
pub fn is_id(&self) -> bool {
match *self {
Memo::Id(_) => true,
_ => false,
}
}
/// Return `true` if memo is `Text`.
pub fn is_text(&self) -> bool {
match *self {
Memo::Text(_) => true,
_ => false,
}
}
/// Return `true` if memo is `Hash`.
pub fn is_hash(&self) -> bool {
match *self {
Memo::Hash(_) => true,
_ => false,
}
}
/// Return `true` if memo is `Return`.
pub fn is_return(&self) -> bool {
match *self {
Memo::Return(_) => true,
_ => false,
}
}
}