Breaking on to new lines? If I have a long line of code that exceeds 80 characters, like this:

$last_response = '&lt;strong&gt;' . t('Last response: ') . '&lt;/strong&gt;' . format_interval((time() - $last), 1) . t(' ago');


Should I break it on to a new line and indent once? I'm sure I've read this in the coding standards somewhere, but now I cannot find where I read it, if I did, like this.

$last_response = '&lt;strong&gt;' . t('Last response: ') . '&lt;/strong&gt;'
  . format_interval((time() - $last), 1) . t(' ago');
The answer is yes, you should break and indent.

For the more details, including exceptions to this rule, see the official Drupal coding standards on line length and wrapping and indenting.

A handy tool to check whether your source code follow the official Drupal codings standards is Coder.  It is also available as SaaS, as part of PAreview.