@ngdoc error
@name $interpolate:unknarg
@fullName Unrecognized MessageFormat extension
@description

The MessageFormat extensions provided by `ngMessageFormat` are currently
limited to "plural" and "select".  The extension that you have used is either
unsupported or invalid.

For more information about the MessageFormat syntax in interpolation
expressions, please refer to MessageFormat extensions section at
{@link guide/i18n#MessageFormat AngularJS i18n MessageFormat}