OptionaldomesticRule for carrier code formatting
Replacement format string using $1, $2, etc.
OptionalleadingCompiled leading digits pattern to determine when to use this format (prefix match: ^pattern, patterns combined with |)
OptionalnationalRule for formatting with national prefix (e.g., "0$1")
OptionalnationalWhether the national prefix is optional when formatting
Compiled pattern to match the national number (anchored: ^pattern$, with capturing groups)
Format descriptor for formatting phone numbers. Maps to NumberFormat in libphonenumber.