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/// Returns the maximum value of a collection.
///
///
/// # Arguments
///
/// * `collection` - The collection to find maximum value.
///
///
/// # Returns
///
/// The maximum value of a collection..
///
/// # Examples
///
/// ```
/// use rufl::collection;
///
/// assert_eq!(Some(3), collection::max(&vec![1, 2, 3, 2]));
///
/// let empty: Vec<i32> = vec![];
/// assert_eq!(None, collection::max(&empty));
///
/// ```
pub fn max<C: AsRef<[T]>, T: PartialOrd + Clone>(collection: &C) -> Option<T> {
let vector = collection.as_ref().to_vec();
match vector.len() {
0 => None,
_ => {
let mut max = &vector[0];
for i in 1..vector.len() {
let val = &vector[i];
if *val > *max {
max = val;
}
// max = cmp::max(max, vector[i])
}
return Some(max.clone());
}
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_max() {
assert_eq!(Some(3), max(&vec![1, 2, 3, 2]));
let empty: Vec<i32> = vec![];
assert_eq!(None, max(&empty));
}
}