tea_core/vec_core/
iter.rs

1use std::marker::PhantomData;
2
3use crate::prelude::*;
4
5/// A trait indicating that a type can be referenced to a Trusted and DoubleEnded iterator.
6/// A trait for types that can be iterated over with a trusted iterator.
7///
8/// This trait extends the `GetLen` trait and provides methods to create
9/// trusted iterators over the implementing type.
10///
11/// # Type Parameters
12///
13/// * `T`: The type of items yielded by the iterator.
14pub trait TIter<T>: GetLen {
15    /// Creates a trusted iterator over the items of this collection.
16    ///
17    /// # Returns
18    ///
19    /// An iterator that implements the `TIterator` trait, yielding items of type `T`.
20    fn titer(&self) -> impl TIterator<Item = T> + '_;
21
22    /// Maps each item in the collection using the provided function.
23    ///
24    /// This method creates a new iterator that applies the given function to
25    /// each item yielded by the original iterator.
26    ///
27    /// # Arguments
28    ///
29    /// * `f`: A function that takes an item of type `T` and returns an item of type `U`.
30    ///
31    /// # Returns
32    ///
33    /// An iterator that yields the mapped items.
34    ///
35    /// # Type Parameters
36    ///
37    /// * `'a`: The lifetime of the reference to `self`.
38    /// * `U`: The type of items yielded by the new iterator.
39    /// * `F`: The type of the mapping function.
40    #[inline]
41    fn map<'a, U, F>(&'a self, f: F) -> impl TIterator<Item = U>
42    where
43        F: FnMut(T) -> U,
44        T: 'a,
45    {
46        self.titer().map(f)
47    }
48}
49
50/// A trait indicating that a type can be converted into a Trusted and DoubleEnded iterator.
51pub trait IntoTIter: IntoIterator
52where
53    Self::IntoIter: TIterator,
54{
55    fn into_titer(self) -> Self::IntoIter
56    where
57        Self: Sized;
58}
59
60impl<I: IntoIterator + GetLen> IntoTIter for I
61where
62    Self::IntoIter: TIterator,
63{
64    #[inline]
65    fn into_titer(self) -> Self::IntoIter {
66        self.into_iter()
67    }
68}
69/// An iterator adapter that wraps a `Vec1View` and converts its items to `Option` types.
70///
71/// This struct provides a way to iterate over a `Vec1View` while converting each item
72/// to an `Option` type. It's particularly useful when working with types that implement
73/// the `IsNone` trait, allowing for a uniform representation of potentially absent values.
74///
75/// # Type Parameters
76///
77/// * `'a`: The lifetime of the reference to the underlying `Vec1View`.
78/// * `V`: The type of the underlying `Vec1View`.
79/// * `T`: The item type of the `Vec1View`.
80///
81/// # Fields
82///
83/// * `view`: A reference to the underlying `Vec1View`.
84/// * `item`: A `PhantomData` to carry the item type `T`.
85pub struct OptIter<'a, V: Vec1View<T>, T> {
86    pub view: &'a V,
87    pub item: PhantomData<T>,
88}
89
90impl<V: Vec1View<T>, T> GetLen for OptIter<'_, V, T> {
91    #[inline]
92    fn len(&self) -> usize {
93        self.view.len()
94    }
95}
96
97impl<V: Vec1View<T>, T: IsNone> TIter<Option<<T as IsNone>::Inner>> for OptIter<'_, V, T> {
98    #[inline]
99    fn titer(&self) -> impl TIterator<Item = Option<<T as IsNone>::Inner>> {
100        self.view.titer().map(|v| v.to_opt())
101    }
102}
103
104impl<'a, T: IsNone + 'a, V: Vec1View<T>> Vec1View<Option<T::Inner>> for OptIter<'a, V, T>
105where
106    for<'b> V::SliceOutput<'b>: TIter<T>,
107{
108    type SliceOutput<'b>
109        = Vec<Option<T::Inner>>
110    where
111        Self: 'b;
112
113    #[inline]
114    fn slice<'b>(&'b self, start: usize, end: usize) -> TResult<Self::SliceOutput<'b>>
115    where
116        T: 'b,
117    {
118        Ok(self
119            .view
120            .slice(start, end)?
121            .titer()
122            .map(|v| v.to_opt())
123            .collect_trusted_to_vec())
124    }
125
126    #[inline]
127    fn get_backend_name(&self) -> &'static str {
128        self.view.get_backend_name()
129    }
130
131    #[inline]
132    unsafe fn uget(&self, index: usize) -> Option<T::Inner> {
133        unsafe { self.view.uget(index).to_opt() }
134    }
135}
136
137impl<'a, V: Vec1View<T>, T: IsNone> IntoIterator for &'a OptIter<'_, V, T> {
138    type Item = Option<T::Inner>;
139    type IntoIter = Box<dyn TrustedLen<Item = Option<T::Inner>> + 'a>;
140    #[inline]
141    fn into_iter(self) -> Self::IntoIter {
142        Box::new(self.titer())
143    }
144}
tea_core/vec_core/iter.rs

tea_core/vec_core/
iter.rs
