func (s *Solidity) makeArgs() []string {
    p := []string{
        "--combined-json", "bin,abi,userdoc,devdoc",
        "--add-std",  // include standard lib contracts
        "--optimize", // code optimizer switched on
    }
    if s.Major > 0 || s.Minor > 4 || s.Patch > 6 {
        p[1] += ",metadata"
    }
    return p
}

func (s *Solidity) makeArgs() []string {
    p := []string{
        "--combined-json", "bin,abi,userdoc,devdoc",
        "--optimize", // code optimizer switched on
    }
    if s.Major > 0 || s.Minor > 4 || s.Patch > 6 {
        p[1] += ",metadata"
    }
    return p
}