feat: adds TryCatch

README.md

@@ -41,6 +41,8 @@ Heavily inspired by rust [std::option](https://doc.rust-lang.org/std/option/inde
       - [unwrap](#unwrap-1)
       - [unwrapErr](#unwrapErr)
       - [unwrapOr](#unwrapOr-1)
+      - [unwrapOrElse](#unwrapOrElse)
+  - [TryCatch](#TryCatch)
 - [Contributing](#Contributing)
 - [Licence](#Licence)
 
@@ -376,6 +378,36 @@ Ok('pizza').unwrapOrElse(err => err.message) // 'pizza'
 Err('pizza with ananas').unwrapOrElse(err => err.message) // 'pizza with ananas'
 ```
 
+## TryCatch
+
+These functions handle try/catch.
+
+```ts
+import { TryCatch, TryCatchAsync } from 'some.js';
+
+TryCatch(
+  (a: number, b: number) => a + b,
+  10,
+  20,
+) // returns Ok(30)
+
+TryCatch(
+  (a: number, b: number) => a + b + c,
+  10,
+  20,
+) // returns Err('c is not defined')
+
+TryCatchAsync(
+  (url: string) => fetch(url).then(r => r.json()),
+  'https://reqres.in/api/users?page=2'
+) // returns Ok({ /* some json data here */ })
+
+TryCatchAsync(
+  (url: string) => fetch(url).then(r => r.document()),
+  'https://reqres.in/api/users?page=2'
+) // returns Err('r.document is not a function)
+```
+
 # Contributing
 
 Read the [contributing guidelines](./CONTRIBUTING.md)

src/TryCatch.ts

@@ -0,0 +1,64 @@
+import { Ok, Err } from "./Result";
+
+export type Fn = () => any;
+export type FnAsync = () => Promise<any>;
+
+/**
+ * Handle sync try/catch.
+ *
+ * ```ts
+ * import { TryCatch, TryCatchAsync } from 'some.js';
+ *
+ * TryCatch(
+ *   (a: number, b: number) => a + b,
+ *   10,
+ *   20,
+ * ) // returns Ok(30)
+ * ```
+ *
+ * @export
+ * @template FnTry
+ * @template K
+ * @param {FnTry} fnTry
+ * @param {...K} args
+ * @returns {(Ok<ReturnType<FnTry>> | Err)}
+ */
+export function TryCatch<FnTry extends (...args: K) => any, K extends any[]>(
+  fnTry: FnTry,
+  ...args: K
+): Ok<ReturnType<FnTry>> | Err {
+  try {
+    return Ok(fnTry.apply(null, args));
+  } catch (error) {
+    return Err(error.message);
+  }
+}
+
+/**
+ * Handle sync try/catch.
+ *
+ * ```ts
+ * TryCatchAsync(
+ *   (url: string) => fetch(url).then(r => r.json()),
+ *   'https://reqres.in/api/users?page=2'
+ * ) // returns Ok({ some json data here })
+ *
+ * ```
+ *
+ * @export
+ * @template FnTry
+ * @template K
+ * @param {FnTry} fnTry
+ * @param {...K} args
+ * @returns {(Promise<Ok<ReturnType<FnTry>> | Err>)}
+ */
+export async function TryCatchAsync<
+  FnTry extends (...args: K) => Promise<any>,
+  K extends any[]
+>(fnTry: FnTry, ...args: K): Promise<Ok<ReturnType<FnTry>> | Err> {
+  try {
+    return Ok(await fnTry.apply(null, args));
+  } catch (error) {
+    return Err(error.message);
+  }
+}

src/__tests__/TryCatch.spec.ts

@@ -0,0 +1,40 @@
+import { TryCatch, TryCatchAsync } from "../TryCatch";
+import { Ok, Err } from "../Result";
+
+describe(`TryCatch`, () => {
+  it("returns the ok fn if does not catch", () => {
+    expect(TryCatch(() => 10)).toStrictEqual(Ok(10));
+  });
+
+  it("can receive a number N of arguments", () => {
+    expect(
+      TryCatch((a: number, b: number) => `received ${a} and ${b}`, 10, 20)
+    ).toStrictEqual(Ok(`received 10 and 20`));
+  });
+
+  it("returns Err if the tryFn catches", () => {
+    expect(
+      TryCatch(
+        // @ts-ignore
+        () => a + 1
+      )
+    ).toStrictEqual(Err("a is not defined"));
+  });
+
+  it("handles async functions", async () => {
+    expect(
+      await TryCatchAsync(
+        (a: number, b: number) => Promise.resolve(a + b),
+        10,
+        20
+      )
+    ).toStrictEqual(Ok(30));
+
+    expect(
+      await TryCatchAsync(
+        // @ts-ignore
+        () => b * 20
+      )
+    ).toStrictEqual(Err("b is not defined"));
+  });
+});