Convert nano time to string return garbage?

[proyb6]

What version of Go are you using (go version)?

1.14.3

Does this issue reproduce with the latest release?

I think earlier may have the same issue, I have checked other repos have used the same approach.

What operating system and processor architecture are you using (go env)?

NA

What did you do?

Converting nano time to string

fmt.Println(string(time.Now().UnixNano()))

What did you expect to see?

As expected number return by nano time.

What did you see instead?

A question mark character

https://play.golang.com/p/7NfnDfYy4_N

[acln0]

string(x) doesn't do what you think it does when x is an integer. It interprets x as a unicode code point and creates a string with the UTF-8 encoding of said code point, if possible. For your particular case, it isn't possible, so you get an encoding of unicode.ReplacementChar instead: https://play.golang.org/p/qLfoV6dj_AK

To format an integer into a string, use the fmt or strconv package.