Add tweak to change articles in title sort pattern

resources/default_tweaks.py

@@ -83,6 +83,15 @@ title_series_sorting = 'library_order'
 # strictly_alphabetic, it would remain "The Client".
 save_template_title_series_sorting = 'library_order'
 
+# Set the list of words that are to be considered 'articles' when computing the
+# title sort strings. The list is a regular expression, with the articles
+# separated by 'or' bars. Comparisons are case insensitive, and that cannot be
+# changed. Changes to this tweak won't have an effect until the book is modified
+# in some way. If you enter an invalid pattern, it is silently ignored.
+# Default: '^(A|The|An)\s+'
+title_sort_articles='^(A|The|An)\s+'
+
+
 # Specify a folder that calibre should connect to at startup using
 # connect_to_folder. This must be a full path to the folder. If the folder does
 # not exist when calibre starts, it is ignored. If there are '\' characters in

src/calibre/ebooks/metadata/__init__.py

@@ -44,7 +44,15 @@ def author_to_author_sort(author):
 def authors_to_sort_string(authors):
     return ' & '.join(map(author_to_author_sort, authors))
 
+try:
+    _title_pat = re.compile(tweaks.get('title_sort_articles',
+                                       r'^(A|The|An)\s+'), re.IGNORECASE)
+except:
+    print 'Error in title sort pattern'
+    import traceback
+    traceback.print_exc()
     _title_pat = re.compile('^(A|The|An)\s+', re.IGNORECASE)
+
 _ignore_starts = u'\'"'+u''.join(unichr(x) for x in range(0x2018, 0x201e)+[0x2032, 0x2033])
 
 def title_sort(title):