rustHow to declare a constant Rust HashMap?

A constant Rust HashMap can be declared using the const keyword.

const MY_HASHMAP: HashMap<&str, i32> = [("a", 1), ("b", 2)].iter().cloned().collect();

This example creates a constant HashMap with two entries, ("a", 1) and ("b", 2). The HashMap is of type HashMap<&str, i32>, meaning it maps strings to integers.

• const: keyword used to declare a constant
• MY_HASHMAP: name of the constant
• HashMap<&str, i32>: type of the constant
• [("a", 1), ("b", 2)]: entries in the HashMap
• iter(): creates an iterator over the entries
• cloned(): clones the entries
• collect(): collects the entries into a HashMap

Helpful links

• Rust HashMap Documentation

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