Page Chapter 3. Module-Specific Settings, Page 28

Location on the page: 
Middle of page, in code block
Error: 

Two instances:

'#default_value' => variable_get('annotate_deletion', 0) // default to Never

and

'#size' => 3

Correction: 

Two instances:

'#default_value' => variable_get('annotate_deletion', 0), // default to Never

and

'#size' => 3,

Description of the Error: 

To adhere to Drupal coding standards, the last array element should be followed by a comma.