i have sample code, which example 1 - 4, where most representing rustlang style and if all four example have same result for performance output or not?
can some one can give me advice for write better code in rustlang.
fn hashmap_test(){
let mut score = HashMap::new();
println!("Insert random score.");
for i in 1..10 { score.insert(format!("Team_{}", i), rand::thread_rng().gen_range(0, 101)); }
// example 1
println!("\nExample filter 1.");
for (key, value) in score.iter().filter(| cltn | *cltn.1 >= 50) {
println!("score : {} is {}", key, value);
}
// example 2
println!("\nExample filter 2.");
for (key, value) in score.iter().filter(| cltn | cltn.1 >= &50) {
println!("score : {} is {}", key, value);
}
// example 3
println!("\nExample filter 3.");
for (key, value) in score.iter().filter(| (key , val) | **val >= 50) {
println!("score : {} is {}", key, value);
}
// example 4
println!("\nExample filter 4.");
for (key, value) in score.iter().filter(| (key , val) | val >= &&50) {
println!("score : {} is {}", key, value);
}
}