use super::Iterable;
use super::IterableItem;
use crate::execution_step::value_types::TracePosOperate;
use crate::execution_step::ValueAggregate;
use crate::foldable_next;
use crate::foldable_prev;
const EXPECT_VALUE_IN_MAP: &str = "value must exist, because length checked before creation and canonicalized stream map can not be modified during iteration";
pub(crate) struct CanonStreamMapIterableIngredients {
values: Vec<ValueAggregate>,
cursor: usize,
}
impl CanonStreamMapIterableIngredients {
pub(crate) fn init(values: Vec<ValueAggregate>) -> Self {
Self { values, cursor: 0 }
}
}
impl<'ctx> Iterable<'ctx> for CanonStreamMapIterableIngredients {
type Item = IterableItem<'ctx>;
fn next(&mut self) -> bool {
foldable_next!(self, self.len())
}
fn prev(&mut self) -> bool {
foldable_prev!(self)
}
fn peek(&'ctx self) -> Option<Self::Item> {
if self.values.is_empty() {
return None;
}
let value = self.values.get(self.cursor).expect(EXPECT_VALUE_IN_MAP);
let result = IterableItem::RefValue((
value.get_result(),
value.get_tetraplet(),
value.get_trace_pos(),
value.get_provenance(),
));
Some(result)
}
fn len(&self) -> usize {
self.values.len()
}
}