Example
// This example creates a macro `set!` that functions similarly to the built-in
// macro vec!
use std::collections::HashSet;
macro_rules! set {
( $( $x:expr ),* ) => { // Match zero or more comma delimited items
{
let mut temp_set = HashSet::new(); // Create a mutable HashSet
$(
temp_set.insert($x); // Insert each item matched into the HashSet
)*
temp_set // Return the populated HashSet
}
};
}
// Usage
let my_set = set![1, 2, 3, 4];
