use std::collections::HashMap; use serde_derive::{Deserialize, Serialize}; use serde_hashkey::to_key; #[derive(Debug, PartialEq, Eq, Serialize, Deserialize)] struct Author { name: String, age: u32, } #[derive(Debug, PartialEq, Eq, Serialize, Deserialize)] struct Book { title: String, author: Author, } fn main() -> Result<(), Box> { let book = Book { title: String::from("Birds of a feather"), author: Author { name: String::from("Noah"), age: 42, }, }; let key = to_key(&book)?; let mut ratings = HashMap::new(); ratings.insert(key.clone(), 5); println!("ratings: {:?}", ratings); println!( "book as json (through key): {}", serde_json::to_string_pretty(&key)? ); println!( "book as json (through original object): {}", serde_json::to_string_pretty(&book)? ); Ok(()) }