From 605a3543468438dfce031d401cb68cb717cda60e Mon Sep 17 00:00:00 2001
From: Yegor Bugayenko <yegor256@gmail.com>
Date: Mon, 17 Apr 2023 10:02:10 +0300
Subject: [PATCH] #7 clear()

---
 src/map.rs | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/src/map.rs b/src/map.rs
index 334076f..4a108ff 100644
--- a/src/map.rs
+++ b/src/map.rs
@@ -181,6 +181,12 @@ impl<K: Copy + PartialEq, V: Clone + Copy, const N: usize> Map<K, V, N> {
         }
         None
     }
+
+    /// Remove all pairs from it, but keep the space intact for future use.
+    #[inline]
+    pub fn clear(&mut self) {
+        self.next = 0;
+    }
 }
 
 #[cfg(test)]
@@ -298,3 +304,12 @@ fn large_map_in_heap() -> Result<()> {
     assert_eq!(0, m.len());
     Ok(())
 }
+
+#[test]
+fn clears_it_up() -> Result<()> {
+    let mut m: Map<&str, i32, 10> = Map::new();
+    m.insert("one", 42);
+    m.clear();
+    assert_eq!(0, m.len());
+    Ok(())
+}