932 pub enum VersionError {  enum
942 impl fmt::Display for VersionError {  implementation
945             VersionError::Exec(err) => write!(f, "`gnuplot --version` failed: {}", err),  in fmt()
946             VersionError::Error(msg) => {  in fmt()
949             VersionError::OutputError => write!(f, "`gnuplot --version` returned invalid utf-8"),  in fmt()
950             VersionError::ParseError(msg) => write!(  in fmt()
958 impl ::std::error::Error for VersionError {  implementation
961             VersionError::Exec(_) => "Execution Error",  in description()
962             VersionError::Error(_) => "Other Error",  in description()
963             VersionError::OutputError => "Output Error",  in description()
964             VersionError::ParseError(_) => "Parse Error",  in description()
970             VersionError::Exec(err) => Some(err),  in cause()
987 pub fn version() -> Result<Version, VersionError> {  in version()
991         .map_err(VersionError::Exec)?;  in version()
994             String::from_utf8(command_output.stderr).map_err(|_| VersionError::OutputError)?;  in version()
995         return Err(VersionError::Error(error));  in version()
998     let output = String::from_utf8(command_output.stdout).map_err(|_| VersionError::OutputError)?;  in version()
1000     parse_version(&output).map_err(|_| VersionError::ParseError(output.clone()))  in version()