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use crate::{
selection::Selection,
state::{EditorState, EvaluationResult},
};
pub enum EvaluationStrategy {
Sequential,
Grouped,
}
pub type MonadicState = (EditorState, EvaluationResult);
pub struct EditorStateMonad {
func: Box<dyn Fn(EditorState) -> MonadicState>,
}
impl EditorStateMonad {
pub fn new(f: impl Fn(EditorState) -> MonadicState + 'static) -> Self {
Self { func: Box::new(f) }
}
pub fn run(&self, initial_state: EditorState) -> MonadicState {
(self.func)(initial_state)
}
pub fn run_with_strategy<E>(
monads: Vec<EditorStateMonad>,
strategy: EvaluationStrategy,
initial_state: EditorState,
) -> Result<MonadicState, E> {
match strategy {
EvaluationStrategy::Sequential => {
let mut state_changes = Vec::new();
let mut last_selection = Selection::empty();
let mut current_state = initial_state;
for monad in monads {
let (new_state, (sel, st_ch)) = monad.run(current_state);
current_state = new_state;
last_selection = sel;
state_changes.extend(st_ch);
}
Ok((current_state, (last_selection, state_changes)))
}
EvaluationStrategy::Grouped => {
panic!("TODO")
}
}
}
}
|
