list_fn/
map.rs

1use super::*;
2
3pub trait MapFn {
4    type Input;
5    type Output;
6    /// Map the given `input` item into an output item.
7    fn map(&self, input: Self::Input) -> Self::Output;
8}
9
10pub struct MapWrap<M: MapFn>(M);
11
12impl<M: MapFn> FlatMapFn for MapWrap<M> {
13    type Input = M::Input;
14    type OutputList = Option<M::Output>;
15    fn map(&self, input: Self::Input) -> Self::OutputList {
16        Some(self.0.map(input))
17    }
18}
19
20pub trait Map: ListFn {
21    fn map<M: MapFn<Input = Self::Item>>(self, m: M) -> FlatMapList<Self, MapWrap<M>> {
22        self.flat_map(MapWrap(m))
23    }
24}
25
26impl<L: ListFn> Map for L {}