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/// Replace the first count n old elements with new elements within the vector.
///
///
/// # Arguments
///
/// * `vec` - The vector to replace.
///
/// * `old` - old item to be replaced.
///
/// * `new` - new item to replace.
///
/// * `n` - the number of old elements bo be replaced.
///
///
///
/// # Examples
///
/// ```
/// use rufl::collection;
///
/// let mut vec = vec!["a", "b", "c", "b"];
///
/// let result = collection::replace_n(&mut vec, "b", "2", 1);
///
/// assert_eq!(vec!["a", "2", "c", "b"], vec);
///
/// ```
pub fn replace_n<T: PartialEq + Clone>(vec: &mut Vec<T>, old: T, new: T, mut n: usize) {
for i in 0..vec.len() {
if vec[i] == old && n != 0 {
vec[i] = new.clone();
n -= 1;
}
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_replace_n() {
let mut vec = vec!["a", "b", "c", "b"];
replace_n(&mut vec, "b", "2", 0);
assert_eq!(vec!["a", "b", "c", "b"], vec);
replace_n(&mut vec, "b", "2", 1);
assert_eq!(vec!["a", "2", "c", "b"], vec);
replace_n(&mut vec, "b", "2", 2);
assert_eq!(vec!["a", "2", "c", "2"], vec);
}
}