> For the complete documentation index, see [llms.txt](https://zeyad-abulaban.gitbook.io/notes/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://zeyad-abulaban.gitbook.io/notes/golang-programming/misc.md).

# Misc

***

## Understanding `_`

It is called the blank identifier. Meaning the value assigned to it should be discarded. Because Go compiler doesn't allow you to create a variable you won't use.

**Let's take this example:**

```go
package main

import (
	"fmt"
	"net"
)

func main() {
	_,err := net.Dial("tcp","www.chegg.com:80")
	if err == nil {
		fmt.Println("it works!")
	}
}

//Ouutput: it works!
```

**Now let's remove the** `_`

```go
package main

import (
	"fmt"
	"net"
)

func main() {
	err := net.Dial("tcp","www.chegg.com:80")
	if err == nil {
		fmt.Println("it works!")
	}
}

//Output: ./main.go:9:6: assignment mismatch: 1 variable but net.Dial returns 2 values
```

**Then we must assign 2 variables, s let's define a variable**

```go
package main

import (
	"fmt"
	"net"
)

func main() {
	abuqasem,err := net.Dial("tcp","www.chegg.com:80")
	if err == nil {
		fmt.Println("it works!")
	}
}

//Output: ./main.go:9:2: abuqasem declared but not used
```

**So to avoid this error we have 2 options:** 1: Use the variable

```go
package main

import (
	"fmt"
	"net"
)

func main() {
	abuqasem,err := net.Dial("tcp","www.chegg.com:80")
	if err == nil && abuqasem != nil {
		fmt.Println("it works!")
	}
}

//Output: it works!
```

2: Use the `_` and make the code cleaner

```go
package main

import (
	"fmt"
	"net"
)

func main() {
	_,err := net.Dial("tcp","www.chegg.com:80")
	if err == nil {
		fmt.Println("it works!")
	}
}

//Output: it works!
```


---

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