Function HandlePopBackCommand

Source/cmListCommand.cxx:197–244

}

bool HandlePopBackCommand(std::vector<std::string> const& args,
                          cmExecutionStatus& status)
{
  assert(args.size() >= 2);

  cmMakefile& makefile = status.GetMakefile();
  auto ai = args.cbegin();
  ++ai; // Skip subcommand name
  std::string const& listName = *ai++;
  auto list = GetList(listName, makefile);

  if (!list) {
    // Can't get the list definition... undefine any vars given after.
    for (; ai != args.cend(); ++ai) {
      makefile.RemoveDefinition(*ai);
    }
    return true;
  }

  if (!list->empty()) {
    if (ai == args.cend()) {
      // No variables are given... Just remove one element.
      list->pop_back();
    } else {
      // Ok, assign elements to be removed to the given variables
      for (; !list->empty() && ai != args.cend(); ++ai) {
        assert(!ai->empty());
        makefile.AddDefinition(*ai, list->back());
        list->pop_back();
      }
      // Undefine the rest variables if the list gets empty earlier...
      for (; ai != args.cend(); ++ai) {
        makefile.RemoveDefinition(*ai);
      }
    }

    makefile.AddDefinition(listName, list->to_string());

  } else if (ai !=
             args.cend()) { // The list is empty, but some args were given
    // Need to *undefine* 'em all, cuz there are no items to assign...
    for (; ai != args.cend(); ++ai) {
      makefile.RemoveDefinition(*ai);
    }
  }

  return true;
}

bool HandlePopFrontCommand(std::vector<std::string> const& args,
                           cmExecutionStatus& status)