Code shared from the Rust Playground

playground.rs

use std::cmp::{Ord, Ordering};
use std::collections::BTreeMap;

#[derive(Debug, Clone, PartialEq, Eq, PartialOrd)]
struct Criteria<T>(Vec<T>);

impl<T> From<Vec<T>> for Criteria<T> {
    fn from(v: Vec<T>) -> Criteria<T> {
        Criteria(v)
    }
}

impl<T: Ord> Ord for Criteria<T> {
    fn cmp(&self, other: &Self) -> Ordering {
    
        for i in 0..(self.0.len().min(other.0.len())) {
    
            if self.0[i] < other.0[i] {
                return Ordering::Less;
            } else if self.0[i] > other.0[i] {
                return Ordering::Greater;
            }
    
        }
    
        self.0.len().cmp(&other.0.len())
    }
}

fn main() {
    let criteria: Vec<Criteria<String>> = vec![
        vec!["test", "ing"],
        vec!["test"],
        vec!["dost", "o"],
        vec!["tost"],
    ]
        .into_iter()
        .map(|vec| Criteria(vec
            .into_iter()
            .map(|s| s.to_owned())
            .collect()
        )).collect();
    
    println!("before: {:?}", criteria);
    
    let mut map: BTreeMap<Criteria<String>, usize> = BTreeMap::new();
    
    for (index, criterion) in criteria.into_iter().enumerate() {
        map.insert(criterion, index);
    }
    
    println!("sorted: {:?}", map.keys());
    
}