text: var metadata                = require('./_metadata')
    , anObject                = require('./_an-object')
    , ordinaryOwnMetadataKeys = metadata.keys
    , toMetaKey               = metadata.key;
  
  metadata.exp({getOwnMetadataKeys: function getOwnMetadataKeys(target /*, targetKey */){
    return ordinaryOwnMetadataKeys(anObject(target), arguments.length < 2 ? undefined : toMetaKey(arguments[1]));
  }});