What Does the Blank Identifier _ Mean in Go

The blank identifier _ in Go tells the compiler to ignore a value, variable, or import, effectively discarding it without causing an unused variable error.

// Ignore the second return value from a function call
file, _ := os.Open("data.txt")

// Import a package for its side effects only
import _ "net/http/pprof"

// Skip a loop index
for _, value := range slice {
    fmt.Println(value)
}

The underscore acts as a trash bin for values you don't need. It lets you write code that compiles cleanly even when you have extra data or imports you aren't using. Think of it as a way to say, "I know this exists, but I don't care about it right now."