file.rs

extern crate itertools;
use itertools::Itertools;
use std::thread;
use std::sync::{Mutex, Arc};

fn is_palindrome(num: u64) -> bool {
    let s = num.to_string();
    s.chars().zip(s.chars().rev()).all(|(i1, i2)| i1 == i2 )
}

fn main() {
    let mut iter = Arc::new(Mutex::new((100..1000).combinations()));
    for _ in 0..8 {
        let iter = iter.clone();
        thread::spawn(move || {
            let mut block = iter.lock().unwrap().take(10000);
            while block.len() > 0 {
                for tup in block {
                    //TODO
                }
                let mut block = iter.lock().unwrap().take(10000);
            }
        });
    }
}

Compiling palindrome v0.1.0 (file:///Users/SumProxy/Projects/rust/palindrome)
src/main.rs:17:25: 17:30 error: no method named `len` found for type `core::iter::Take<itertools::adaptors::Combinations<core::ops::Range<_>>>` in the current scope
src/main.rs:17             while block.len() > 0 {
                                       ^~~~~
note: in expansion of closure expansion
src/main.rs:15:23: 23:10 note: expansion site
note: in expansion of for loop expansion
src/main.rs:13:5: 24:6 note: expansion site
src/main.rs:17:25: 17:30 note: the method `len` exists but the following trait bounds were not satisfied: `itertools::adaptors::Combinations<core::ops::Range<_>> : core::iter::ExactSizeIterator`
error: aborting due to previous error
Could not compile `palindrome`.

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