feat: Issue: Loop Struct Slice (#31)

Author: hhow09

examples.txt

@@ -11,6 +11,7 @@ Methods | methods
 Channel: Merge | channel-merge
 Reflection | reflection
 Issue: Goroutine Leak | issue-goroutine-leak
+Issue: Loop Struct Slice | issue-loop-struct-slice
 encoding/json | encoding-json
 Url Parsing | url-parsing
 http Request | http-req

examples/issue-loop-struct-slice/issue-loop-struct-slice.go

@@ -0,0 +1,59 @@
+// interview questions:
+//
+// What is expected output?
+//
+// How to fix this code?
+
+package main
+
+import "fmt"
+
+func main() {
+	type player struct {
+		name  string
+		score int
+	}
+	players := []player{
+		{"Bob", 10},
+		{"Alice", 207},
+	}
+
+	for _, p := range players {
+		p.score += 10
+	}
+
+	for _, p := range players {
+		fmt.Printf("player %s has score %d\n", p.name, p.score)
+	}
+
+	// (End of Question)
+	// ----------
+
+	// Explaination:
+	// The player struct is stored in the backing array of the slice players
+	//
+	// `p` is actually only a copy of the original player
+	for _, p := range players {
+		p.score += 10
+	}
+
+	// How to fix it?
+
+	fmt.Println("---- After fix ------")
+	// Directly access the player in the slice
+	for i := range players {
+		players[i].score += 10
+	}
+
+	for _, p := range players {
+		fmt.Printf("player %s has score %d\n", p.name, p.score)
+	}
+
+	// Output:
+	//
+	// player Bob has score 20
+	//
+	// player Alice has score 217
+}
+
+// Reference: [Should you use slices of pointers to structs?](https://www.willem.dev/articles/slice-of-pointers-structs/)

examples/issue-loop-struct-slice/issue-loop-struct-slice.hash

@@ -0,0 +1,2 @@
+1acf36d67df9c219102a45e722d1cbb38dbd8ce5
+b5YAS_z1uop

examples/issue-loop-struct-slice/issue-loop-struct-slice.sh

@@ -0,0 +1,5 @@
+player Bob has score 10
+player Alice has score 207
+---- After fix ------
+player Bob has score 20
+player Alice has score 217