use crate::{mutable::SPACE, Time};use bstr::{BStr, BString, ByteSlice};use quick_error::quick_error;use std::io; /// A mutable signature is created by an actor at a certain time.////// Note that this is not a cryptographical signature.#[derive(PartialEq, Eq, Debug, Hash, Ord, PartialOrd, Clone)]#[cfg_attr(feature = "serde1", derive(serde::Serialize, serde::Deserialize))]pub struct Signature {    /// The actors name.    pub name: BString,    /// The actor's email.    pub email: BString,    /// The time stamp at which the signature is performed.    pub time: Time,} quick_error! {    /// The Error produced in by [`Signature::write_to()`].    #[derive(Debug)]    #[allow(missing_docs)]    pub enum Error {        IllegalCharacter {            display("Signature name or email must not contain '<', '>' or \\n")        }    }} impl From<Error> for io::Error {    fn from(err: Error) -> Self {        io::Error::new(io::ErrorKind::Other, err)    }} /// Outputimpl Signature {    /// Serialize this instance to `out` in the git serialization format for actors.    pub fn write_to(&self, mut out: impl io::Write) -> io::Result<()> {        out.write_all(validated_token(self.name.as_bstr())?)?;        out.write_all(SPACE)?;        out.write_all(&b"<"[..])?;        out.write_all(validated_token(self.email.as_bstr())?)?;        out.write_all(&b"> "[..])?;        self.time.write_to(out)?;        Ok(())    }} fn validated_token(name: &BStr) -> Result<&BStr, Error> {    if name.find_byteset(b"<>\n").is_some() {        return Err(Error::IllegalCharacter);    }    Ok(name)}