Common Go Pitfalls Every PHP Developer Should Avoid

After five years of PHP development, the author transitioned to Go and identified several recurring mistakes that PHP developers often encounter when writing Go code. This article lists six common pitfalls and provides corrected examples.

1. Function Definition Syntax

Problem: Placing the opening brace on a new line after the function name causes a syntax error.

func main(){
    fmt.Println("php是世界上最好的语言")
}

2. Map Definition and Initialization

Problem: Declaring a map variable without allocating memory leads to a runtime panic.

func main(){
    m := make(map[string]string, 2)
    m["php"] = "世界上最好的语言"
    m["go"] = "世界上最好的语言"
    fmt.Println(m)
}

3. JSON Struct Export

Problem: Struct fields are unexported (lower‑case), so json.Marshal produces empty output.

type Student struct {
    Id    int
    Name  string
    Score int
}

func main(){
    s := Student{1, "小明", 99}
    jsonS, _ := json.Marshal(s)
    fmt.Println(string(jsonS))
}

4. Modifying Elements Inside a Loop

Problem: Using the value variable from range does not modify the underlying slice.

func main(){
    data := []int{1, 2, 3}
    for i := range data {
        data[i] += 1
    }
    fmt.Println(data)
}

5. Array vs. Slice Parameter Passing

Problem: Arrays are passed by value, so changes inside a function do not affect the original array.

func change(data []int){
    data[0] = 4
}

func main(){
    data := []int{1, 2}
    change(data)
    fmt.Println(data) // prints [4 2]
}

6. Variable Shadowing with :=

Problem: Using := inside an if block creates a new variable that does not affect the outer one.

func main(){
    flag := 1
    if true {
        flag = 2
        flag++
    }
    fmt.Println(flag) // prints 3
}

These examples illustrate typical beginner errors when moving from PHP to Go and demonstrate the idiomatic ways to write correct Go code.

Link: https://www.cnblogs.com/lmz-blogs/p/16352023.html