Check to prevent a length less than 0

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Metadata

ID: go-best-practices/check-len

Language: Go

Severity: Warning

Category: Best Practices

Description

In Go, the built-in len() function returns the length of a slice, map, or string, and it never produces a negative value. The length of any data structure in Go is always a non-negative integer.

Hence, the condition len(mySlice) < 0 will always evaluate to false, and the code block within the if statement will never execute.

To fix this issue, you should remove the unnecessary check for len(mySlice) < 0:

Non-Compliant Code Examples

func main() {
    if len(mySlice) < 0 {
        // never occurs
    }
}

Compliant Code Examples

func main() {
    if len(mySlice) == 0 {
        
    }
}