add: custom enum

test/basic/enum_test.go

@@ -0,0 +1,33 @@
+package main
+
+import (
+	"fmt"
+	"testing"
+)
+
+type Day int
+
+const (
+	Sunday Day = iota
+	Monday
+	Tuesday
+	Wednesday
+	Thursday
+	Friday
+	Saturday
+)
+
+// 定义 Day 类型的 String 方法
+func (d Day) String() string {
+	names := []string{"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"}
+	if d < Sunday || d > Saturday {
+		return "Unknown"
+	}
+	return names[d]
+}
+
+func TestEnum(t *testing.T) {
+	fmt.Println(Sunday)    // 输出: Sunday
+	fmt.Println(Wednesday) // 输出: Wednesday
+	fmt.Println(Day(7))    // 输出: Unknown
+}