Check if any value in a Rust HashMap is greater than zero

Question

I want to check if a HashMap<i32, i32> contains any values greater than zero. I have this code:

let has_demand = minimums.iter().any(|*x| x > 0)

which fails. The problem is with |*x|, but I don't know what to put there.

Answer 1

Bad syntax. You should use &x, which is a reference (not *x, which is a dereference).

It is a HashMap (not a Vec), so to check values, you need to iterate through the values (not the entire HashMap).

Example code:

let value_exists = hashmap.values().any(|&x| x > 0);

Please check out the docs:

• Iterator::any

• HashMap::values