-EditClipCommand::EditClipCommand(ProjectList *list, const QString &id, QMap <QString, QString> oldparams, QMap <QString, QString> newparams, bool doIt, QUndoCommand * parent) :
+EditClipCommand::EditClipCommand(ProjectList *list, const QString &id, const QMap <QString, QString> &oldparams, const QMap <QString, QString> &newparams, bool doIt, QUndoCommand * parent) :