itertools_wild/
lib.rs

1//! Itertools-wild — extra wild iterator adaptors, wild functions and wild macros.
2//!
3//! To use the iterator methods in this crate, import the [`ItertoolsWild` trait](./trait.ItertoolsWild.html):
4//!
5//! ```ignore
6//! use itertools_wild::ItertoolsWild;
7//! ```
8//!
9//! ## Rust Version
10//!
11//! This version of itertools-wild requires wild Rust
12//!
13#![doc(html_root_url="https://docs.rs/itertools-wild/")]
14
15extern crate either;
16extern crate itertools;
17
18pub mod adaptors;
19pub mod special;
20
21use adaptors::{
22    ClampToExactLength,
23    AssertExactSize,
24};
25
26pub trait ItertoolsWild : Iterator {
27    /// Assert that the iterator has an exact size hint; the result
28    /// is an iterator that produces the same sequence as usual but also
29    /// implements `ExactSizeIterator`
30    ///
31    /// Note that this is not anything like `unsafe`, since it's not related
32    /// to memory safety -- only logical consistency.
33    ///
34    /// The `AssertExactSize` adaptor will use **debug assertions** to check
35    /// the iterator's actual length.
36    fn assert_exact_size(self, size: usize) -> AssertExactSize<Self>
37        where Self: Sized,
38    {
39        AssertExactSize {
40            iter: self,
41            size: size,
42        }
43    }
44
45    /// Clamp an iterator to an exact length
46    ///
47    /// The adapted iterator never produces more than the `length` amount
48    /// of elements. If the underlying iterator would end short of that,
49    /// the closure `filler` is called to supply elements up until the
50    /// specific `length`.
51    ///
52    /// This iterator can be trusted to have the exact length, and it is fused.
53    fn clamp_to_exact_length<F>(self, length: usize, filler: F) -> ClampToExactLength<Self, F>
54        where Self: Sized,
55              F: FnMut(usize) -> Self::Item,
56    {
57        ClampToExactLength {
58            iter: self.fuse(),
59            index: 0,
60            size: length,
61            filler: filler,
62        }
63    }
64
65}
66
67
68impl<I> ItertoolsWild for I where I: Iterator { }
itertools_wild/lib.rs

itertools_wild/
lib.rs
