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use ;
use Debug;
use crate::;
/// In CQRS (and Domain Driven Design) an `Aggregate` is the
/// fundamental component that encapsulates the state and application
/// logic (aka business rules) for the application. An `Aggregate` is
/// always an entity along with all objects associated with it.
///
/// # Examples
/// ```rust
/// use serde::{
/// Deserialize,
/// Serialize,
/// };
/// use std::fmt::Debug;
///
/// use cqrs_es2::{
/// example_impl::{
/// AddressUpdated,
/// CustomerCommand,
/// CustomerEvent,
/// EmailUpdated,
/// NameAdded,
/// },
/// Error,
/// IAggregate,
/// ICommandHandler,IEventHandler
/// };
///
/// #[derive(
/// Debug,
/// PartialEq,
/// Default,
/// Clone,
/// Serialize,
/// Deserialize
/// )]
/// struct Customer {
/// customer_id: String,
/// name: String,
/// email: String,
/// pub addresses: Vec<String>,
/// }
///
/// impl IAggregate<CustomerCommand, CustomerEvent> for Customer {
/// fn aggregate_type() -> &'static str {
/// "customer"
/// }
/// }
///
/// impl ICommandHandler<CustomerCommand, CustomerEvent> for Customer {
/// fn handle(
/// &self,
/// command: CustomerCommand,
/// ) -> Result<Vec<CustomerEvent>, Error> {
/// match command {
/// CustomerCommand::AddCustomerName(payload) => {
/// if self.name.as_str() != "" {
/// return Err(Error::new(
/// "a name has already been added for this \
/// customer",
/// ));
/// }
///
/// let payload = NameAdded {
/// changed_name: payload.changed_name,
/// };
///
/// Ok(vec![CustomerEvent::NameAdded(payload)])
/// },
/// CustomerCommand::UpdateEmail(payload) => {
/// let payload = EmailUpdated {
/// new_email: payload.new_email,
/// };
///
/// Ok(vec![CustomerEvent::EmailUpdated(
/// payload,
/// )])
/// },
/// CustomerCommand::AddAddress(payload) => {
/// if self
/// .addresses
/// .iter()
/// .any(|i| payload.new_address.eq(i))
/// {
/// return Err(Error::new(
/// "this address has already been added \
/// for this customer",
/// ));
/// }
///
/// let payload = AddressUpdated {
/// new_address: payload.new_address,
/// };
///
/// Ok(vec![CustomerEvent::AddressUpdated(
/// payload,
/// )])
/// },
/// }
/// }}
///
/// impl IEventHandler<CustomerEvent> for Customer {
/// fn apply(
/// &mut self,
/// event: &CustomerEvent,
/// ) {
/// match event {
/// CustomerEvent::NameAdded(payload) => {
/// self.name = payload.changed_name.clone();
/// },
/// CustomerEvent::EmailUpdated(payload) => {
/// self.email = payload.new_email.clone();
/// },
/// CustomerEvent::AddressUpdated(payload) => {
/// self.addresses
/// .push(payload.new_address.clone())
/// },
/// }
/// }
/// }
/// ```