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Table of Contents
Ignoring Unused Return Values
Using _ to Avoid Unused Variable Errors
When Not to Use _
Home Backend Development Golang What is the _ blank identifier in golang

What is the _ blank identifier in golang

Jul 13, 2025 am 01:43 AM

In Go, blank identifiers\_ are used to ignore values. Common uses include ignoring unwanted return values, avoiding unused variable errors, and importing packages that require only side effects. For example, use \_ to ignore the error return value of strconv.Atoi, \_ := strconv.Atoi("123"); ignore the index for \_, item := range items in the range loop; or declare the variable x := 42 and use \_ = x to avoid compilation errors; it can also be used to import database driver import \_ "github.com/go-sql-driver/mysql". However, you should use it with caution to avoid hiding errors or reducing code readability, and multiple uses do not conflict with each other.

What is the _ blank identifier in golang

In Go, the blank identifier _ is a special name that can be used to ignore values in various contexts. It's not a keyword, but rather a convention used by developers to signal that a value or variable isn't going to be used.

What is the _ blank identifier in golang

This comes in handy when you're working with functions or operations that return multiple values, and you only care about some of them.

What is the _ blank identifier in golang

Ignoring Unused Return Values

One of the most common uses of _ is to ignore return values you don't need. For example:

 value, _ := strconv.Atoi("123")

Here, we're converting a string to an integer. The second return value is an error, but if for some reason we're confident the input is always valid (like in this case), we can safely ignore it using _ .

What is the _ blank identifier in golang

You might also see this when ranged over a slice or map and not needing the index:

 for _, item := range items {
    fmt.Println(item)
}

The _ tells anyone reading the code that the index isn't important here — it's just being ignored.


Using _ to Avoid Unused Variable Errors

Go doesn't allow unused variables, which helps keep your code clean. But sometimes during development, you might declare a variable temporarily and not use it yet. In such cases, using _ can help avoid compilation errors.

For example:

 x := 42
_ = x

This tells the compiler that you're aware of the variable but don't intend to use it right now.

Another situation is importing packages just for their side effects (like database drivers):

 import _ "github.com/go-sql-driver/mysql"

Here, the package is imported for its init() function, but you don't need to refer to it directly in your code.


When Not to Use _

While _ is useful, it's best used sparingly. Ignoring errors or values without thinking can hide bugs or make code harder to understand.

  • Avoid ignoring errors unless you're certain they can't happen.
  • Don't use _ as a way to silence linter warnings long-term — fix the issue or explicitly explain why it's safe to ignore.

Also, note that _ is treated specially by the Go compiler. Unlike other variables, multiple uses of _ don't conflict — each one is considered a separate placeholder.


So yeah, the blank identifier is a small but powerful tool in Go that helps reduce noise and enforce good practices. Just don't overdo it — clarity still matters more than convenience.

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