mirror of https://github.com/rust-lang/rust
36 lines
1015 B
Rust
36 lines
1015 B
Rust
use std::any::TypeId;
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use std::collections::HashMap;
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use std::hash::Hash;
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trait State {
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type EventType;
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fn get_type_id_of_state(&self) -> TypeId;
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}
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struct StateMachine<EventType: Hash + Eq> {
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current_state: Box<dyn State<EventType = EventType>>,
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transition_table:
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HashMap<TypeId, HashMap<EventType, fn() -> Box<dyn State<EventType = EventType>>>>,
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}
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impl<EventType: Hash + Eq> StateMachine<EventType> {
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fn inner_process_event(&mut self, event: EventType) -> Result<(), i8> {
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let new_state_creation_function = self
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.transition_table
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.iter()
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.find(|(&event_typeid, _)| event_typeid == self.current_state.get_type_id_of_state())
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.ok_or(1)?
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.1
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.iter()
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.find(|(&event_type, _)| event == event_type)
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//~^ ERROR cannot move out of a shared reference
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.ok_or(2)?
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.1;
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self.current_state = new_state_creation_function();
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Ok(())
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}
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}
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fn main() {}
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