[jflwyasdf]

This is how I would do it.

  Go: *string

  Java: Option<String> or @Nullable String

  Rust: Option<String>

  TypeScript: string | undefined (or string | null)

[golergka]

The problem is, not all of these languages think that "" and null are equal.

[codebje]

I might choose to rephrase that as "the problem is, some of these languages think that "" and null are equal." :-)