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use std::cmp::{min, max};
pub fn clamp<T: Ord>(val: T, lower: T, upper: T) -> T{
max(min(val, upper), lower)
}
pub fn strip_prefix<'a>(txt: &'a str, prefix: &'a str) -> Option<&'a str> {
if txt.starts_with(prefix) {
Some(txt.split_at(prefix.len()).1)
} else {
None
}
}
#[macro_export]
macro_rules! hashmap {
( $($key:expr => $value:expr ),* ) => {{
#[allow(unused_mut)]
let mut h = std::collections::HashMap::new();
$(
h.insert($key, $value);
)*
h
}}
}
#[cfg(test)]
mod tests {
use std::collections::HashMap;
#[test]
fn test_hashmap_macro() {
let mut h = hashmap!("hello" => 1, "world" => 2);
assert_eq!(h.remove("hello"), Some(1));
assert_eq!(h.remove("world"), Some(2));
assert!(h.is_empty());
let h2: HashMap<i32, usize> = hashmap!();
assert!(h2.is_empty());
assert_eq!(h2, HashMap::new());
}
}
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