Default never type for MutableHasMap.empty & MutableList.empty (#4768)

Author: KhraksMamtsov

.changeset/friendly-geese-boil.md

@@ -0,0 +1,5 @@
+---
+"effect": minor
+---
+
+Default `never` type has been added to `MutableHasMap.empty` & `MutableList.empty` ctors

packages/effect/src/MutableHashMap.ts

@@ -102,7 +102,7 @@ class BucketIterator<K, V> implements Iterator<[K, V]> {
  * @since 2.0.0
  * @category constructors
  */
-export const empty = <K, V>(): MutableHashMap<K, V> => {
+export const empty = <K = never, V = never>(): MutableHashMap<K, V> => {
   const self = Object.create(MutableHashMapProto)
   self.referential = new Map()
   self.buckets = new Map()

packages/effect/src/MutableList.ts

@@ -97,7 +97,7 @@ const makeNode = <T>(value: T): LinkedListNode<T> => ({
  * @since 2.0.0
  * @category constructors
  */
-export const empty = <A>(): MutableList<A> => {
+export const empty = <A = never>(): MutableList<A> => {
   const list = Object.create(MutableListProto)
   list.head = undefined
   list.tail = undefined