feat: add to to fx

src/Lazy/fx.ts

@@ -40,6 +40,22 @@ class FxAsyncIterable<A> {
     return this.asyncIterable[Symbol.asyncIterator]();
   }
 
+  /**
+   * It takes a user-defined function that transforms the current object and returns the result of that transformation.
+   *
+   * @example
+   * ```ts
+   * const arrSize = await fx([5, 2, 3, 1, 4, 5, 3])
+   *   .toAsync()
+   *   .filter((n) => n % 2 === 1)
+   *   .map((n) => n * 10)
+   *   .to((iterable) => size(uniq(iterable)));
+   * ```
+   */
+  to<R>(converter: (asyncIterable: this) => R): R {
+    return converter(this);
+  }
+
   /**
    * Returns AsyncIterable of values by running each applying `f`.
    *
@@ -301,6 +317,24 @@ export class FxIterable<A> {
     return this.iterable[Symbol.iterator]();
   }
 
+  /**
+   * It takes a user-defined function that transforms the current object and returns the result of that transformation.
+   *
+   *
+   * @example
+   * ```ts
+   * const size = fx([5, 2, 3, 1, 4, 5, 3])
+   *  .filter(n => n % 2 === 1)
+   *  .map(n => n * 10)
+   *  .to(iterable => new Set(iterable)) // convert set
+   *  .add(10)
+   *  .size;
+   * ```
+   */
+  to<R>(converter: (iterable: this) => R): R {
+    return converter(this);
+  }
+
   /**
    * Returns Iterable of values by running each applying `f`.
    *

test/Lazy/fx.spec.ts

@@ -1,4 +1,4 @@
-import { fx, toArray, toAsync } from "../../src";
+import { fx, size, toArray, toAsync, uniq } from "../../src";
 
 describe("fx", function () {
   describe("sync", function () {
@@ -16,6 +16,15 @@ describe("fx", function () {
         .toArray();
       expect(res).toEqual([11, 12, 13, 14, 15]);
     });
+
+    it("`to` method", function () {
+      const arrSize = fx([5, 2, 3, 1, 4, 5, 3])
+        .filter((n) => n % 2 === 1)
+        .map((n) => n * 10)
+        .to((iterable) => new Set(iterable))
+        .add(10).size;
+      expect(arrSize).toEqual(3);
+    });
   });
 
   describe("async", () => {
@@ -39,5 +48,15 @@ describe("fx", function () {
         .toArray();
       expect(res2).toEqual([11, 12, 13, 14, 15]);
     });
+
+    it("`to` method", async function () {
+      const arrSize = await fx([5, 2, 3, 1, 4, 5, 3])
+        .toAsync()
+        .filter((n) => n % 2 === 1)
+        .map((n) => n * 10)
+        .to((iterable) => size(uniq(iterable)));
+
+      expect(arrSize).toEqual(3);
+    });
   });
 });