Merge pull request moonbitlang#448 from yj-qin/linked-hashmap-api

Tweak LinkedHashMap

linked_hashmap/impl_test.mbt

@@ -332,3 +332,8 @@ test "linked list" {
   m.remove("four")
   inspect(m.debug_linked_list(), content="end")?
 }
+
+test "to_array" {
+  let map = LinkedHashMap::[(1, "one"), (2, "two"), (3, "three")]
+  inspect(map.to_array(), content="[(1, one), (2, two), (3, three)]")?
+}

linked_hashmap/linked_hashmap.mbti

@@ -23,6 +23,7 @@ impl LinkedHashMap {
   remove[K : Hash + Eq, V](Self[K, V], K) -> Unit
   set[K : Hash + Eq, V](Self[K, V], K, V) -> Unit
   size[K, V](Self[K, V]) -> Int
+  to_array[K, V](Self[K, V]) -> Array[Tuple[K, V]]
 }
 
 // Traits

linked_hashmap/moon.pkg.json

@@ -7,5 +7,5 @@
     "moonbitlang/core/array",
     "moonbitlang/core/option"
   ],
-  "test-import": ["moonbitlang/core/string", "moonbitlang/core/assertion"]
+  "test-import": ["moonbitlang/core/string", "moonbitlang/core/assertion", "moonbitlang/core/tuple"]
 }

linked_hashmap/utils.mbt

@@ -83,17 +83,15 @@ pub fn iteri[K, V](self : LinkedHashMap[K, V], f : (Int, K, V) -> Unit) -> Unit
   }
 }
 
-/// Clear the map, removing all key-value pairs. Keeps the allocated space.
+/// Clears the map, removing all key-value pairs. Keeps the allocated space.
 pub fn clear[K, V](self : LinkedHashMap[K, V]) -> Unit {
-  for i = 0; i < self.capacity; i = i + 1 {
-    self.entries[i] = Empty
-  }
+  self.entries.fill(Empty)
   self.size = 0
   self.head = None
   self.tail = None
 }
 
-/// Return the iterator of the hash map, provide elements in the order of insertion.
+/// Returns the iterator of the hash map, provide elements in the order of insertion.
 pub fn as_iter[K, V](self : LinkedHashMap[K, V]) -> @iter.Iter[(K, V)] {
   @iter.Iter::_unstable_internal_make(
     fn(yield) {
@@ -109,3 +107,16 @@ pub fn as_iter[K, V](self : LinkedHashMap[K, V]) -> @iter.Iter[(K, V)] {
     },
   )
 }
+
+/// Converts the hash map to an array.
+pub fn to_array[K, V](self : LinkedHashMap[K, V]) -> Array[(K, V)] {
+  let arr = []
+  loop self.head {
+    Some(Valid(~key, ~value, ~next, ..)) => {
+      arr.push((key, value))
+      continue next
+    }
+    _ => break
+  }
+  arr
+}