From a81b61ecf247734bb9280b320eb882feb84d6335 Mon Sep 17 00:00:00 2001
From: A-yon Lee <i@hyurl.com>
Date: Thu, 2 Jan 2025 02:55:19 +0800
Subject: [PATCH] add `result` package

---
 result/example_test.go | 46 ++++++++++++++++++++++++++++++++++++++++++
 result/result.go       | 30 +++++++++++++++++++++++++++
 2 files changed, 76 insertions(+)
 create mode 100644 result/example_test.go
 create mode 100644 result/result.go

diff --git a/result/example_test.go b/result/example_test.go
new file mode 100644
index 0000000..3865996
--- /dev/null
+++ b/result/example_test.go
@@ -0,0 +1,46 @@
+package result_test
+
+import (
+	"fmt"
+	"strconv"
+
+	"github.com/ayonli/goext/result"
+)
+
+func ExampleWrap() {
+	mathAdd := func(input1 string, input2 string) (int, error) {
+		return result.Wrap(func() (int, error) {
+			num1 := result.Unwrap(strconv.Atoi(input1))
+			num2 := result.Unwrap(strconv.Atoi(input2))
+			return num1 + num2, nil
+		})
+	}
+
+	res, err := mathAdd("10", "20")
+	if err != nil {
+		fmt.Println(err)
+	} else {
+		fmt.Println(res)
+	}
+	// Output:
+	// 30
+}
+
+func ExampleUnwrap() {
+	mathAdd := func(input1 string, input2 string) (int, error) {
+		return result.Wrap(func() (int, error) {
+			num1 := result.Unwrap(strconv.Atoi(input1))
+			num2 := result.Unwrap(strconv.Atoi(input2))
+			return num1 + num2, nil
+		})
+	}
+
+	res, err := mathAdd("10", "20")
+	if err != nil {
+		fmt.Println(err)
+	} else {
+		fmt.Println(res)
+	}
+	// Output:
+	// 30
+}
diff --git a/result/result.go b/result/result.go
new file mode 100644
index 0000000..f37d1c5
--- /dev/null
+++ b/result/result.go
@@ -0,0 +1,30 @@
+package result
+
+import (
+	"errors"
+	"fmt"
+)
+
+func Wrap[R any](fn func() (value R, err error)) (value R, err error) {
+	defer func() {
+		if re := recover(); re != nil {
+			if _err, ok := re.(error); ok {
+				err = _err
+			} else if str, ok := re.(string); ok {
+				err = errors.New(str)
+			} else {
+				err = errors.New(fmt.Sprint(re))
+			}
+		}
+	}()
+
+	return fn()
+}
+
+func Unwrap[R any](value R, err error) R {
+	if err != nil {
+		panic(err)
+	}
+
+	return value
+}