Slicing a stream in Rust

take, skip and their while variants cut an iterator down without a loop.

fn main() {
    let nums: Vec<i32> = (1..=10).collect();

    let head: Vec<&i32> = nums.iter().take(3).collect();
    let tail: Vec<&i32> = nums.iter().skip(7).collect();
    println!("{:?} {:?}", head, tail);

    let rising: Vec<&i32> = nums.iter().take_while(|n| **n < 5).collect();
    println!("{:?}", rising);

    let joined: Vec<i32> = (1..3).chain(90..92).collect();
    println!("{:?}", joined);
}

How it works

take stops after n items, skip drops the first n.
take_while stops at the first item that fails the test.
chain runs one iterator after another.

Keywords and builtins used here

Vec
fn
i32
let
main

The run, in numbers

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Type this snippet

Step 3 of 5 in Adapters, step 3 of 14 in Iterators & closures.

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