feat: add HashMap.HashMap.Entry utility type (#3618)

.changeset/chilled-hotels-sniff.md

@@ -0,0 +1,5 @@
+---
+"effect": minor
+---
+
+Adds HashMap.HashMap.Entry type helper

packages/effect/dtslint/HashMap.ts

@@ -1,6 +1,7 @@
-import { pipe } from "effect/Function"
+import { hole, pipe } from "effect/Function"
 import * as HashMap from "effect/HashMap"
 import * as Predicate from "effect/Predicate"
+import type * as Types from "effect/Types"
 
 declare const hmLiterals: HashMap.HashMap<"k", "v">
 declare const numbers: HashMap.HashMap<string, number>
@@ -23,6 +24,13 @@ export type K = HashMap.HashMap.Key<typeof hmLiterals>
 // $ExpectType "v"
 export type V = HashMap.HashMap.Value<typeof hmLiterals>
 
+// -------------------------------------------------------------------------------------
+// HashMap.Entry
+// -------------------------------------------------------------------------------------
+
+// $ExpectType ["k", "v"]
+hole<Types.Simplify<HashMap.HashMap.Entry<typeof hmLiterals>>>()
+
 // -------------------------------------------------------------------------------------
 // filter
 // -------------------------------------------------------------------------------------

packages/effect/src/HashMap.ts

@@ -66,6 +66,22 @@ export declare namespace HashMap {
    * @category type-level
    */
   export type Value<T extends HashMap<any, any>> = [T] extends [HashMap<infer _K, infer _V>] ? _V : never
+
+  /**
+   * This type-level utility extracts the entry type `[K, V]` from a `HashMap<K, V>` type.
+   *
+   * @example
+   * import { HashMap } from "effect"
+   *
+   * declare const hm: HashMap.HashMap<string, number>
+   *
+   * // $ExpectType [string, number]
+   * type V = HashMap.HashMap.Entry<typeof hm>
+   *
+   * @since 3.9.0
+   * @category type-level
+   */
+  export type Entry<T extends HashMap<any, any>> = [Key<T>, Value<T>]
 }
 
 /**