# PTParsedIdentifier and PTIdentifierList

`PTParsedIdentifier` pairs an `Id` with the [`Loc`](sourceloc.md) it was parsed at - a name plus "where it came from," for error messages such as a duplicate terminal name in [`PTSubcircuitDefinition`](ptsubckt.md)'s `verify()`. Unlike most types in the [circuit representation API](parseroutput.md) it's freely copyable, since it's just two small values.

`PTIdentifierList` is `std::vector<PTParsedIdentifier>`, used for terminal lists, global/ground node lists, and [`PTCommand`](ptcommand.md)'s bareword keyword list. Its `operator<<` prints an `Id::none` entry as `<null>` - the convention for an instance terminal deliberately left unconnected.
