Drupal 7: Entity metadata wrappers

module.php

<?php
//@see: https://drupal.org/node/1021556

$wrapper = entity_metadata_wrapper('node', $node);
$wrapper->author->mail->value();

$wrapper->author->mail->set('[email protected]');
$wrapper->author->mail = '[email protected]';

// Unified way of getting $node->title, $user->name, ...
$wrapper->label();
// Unified way of getting $node->nid, $user->uid, ...
$wrapper->getIdentifier();
// Unified way of getting $node->type, ...
$wrapper->getBundle();

foreach ($wrapper->field_taxonomy_terms->getIterator() as $delta => $term_wrapper) {
  // $term_wrapper may now be accessed as a taxonomy term wrapper.
  $label = $term_wrapper->label->value();
}

$wrapper->save();