old.js

// Remove completed and skipped items.
// REFACTOR: Consider doing this in the visual.
// Different visuals may want to use these items.
var removedCompletedItems = 0,
    removedSkippedItems   = 0;

_.values(MemoryBank.items).forEach(function (item) {
  if (item.memories.completed) {
    delete MemoryBank.items[item.id];
    removedCompletedItems += 1;
  }
  if (item.memories.skipped) {
    delete MemoryBank.items[item.id];
    removedSkippedItems += 1;
  }
});

Logger.info("MemoryBank", removedCompletedItems + " completed items removed.",
                          removedSkippedItems + " skipped items removed.",
                          _.size(MemoryBank.items) + " items remain.");