nationalPrefixTransformRule property
This field is only populated and used under very rare situations. For example, mobile numbers in Argentina are written in two completely different ways when dialed in-country and out-of-country (e.g. 0343 15 555 1212 is exactly the same number as +54 9 343 555 1212). This field is used together with national_prefix_for_parsing to transform the number into a particular representation for storing in the phonenumber proto buffer in those rare cases.
Implementation
@$pb.TagNumber(16)
$core.String get nationalPrefixTransformRule => $_getSZ(14);