+ENTITY_SUBSTITUTIONS = [
+ (u'---', u'—'),
+ (u'--', u'–'),
+ (u'...', u'…'),
+ (u',,', u'„'),
+ (u'"', u'”'),
+]
+
+
+def substitute_entities(context, text):
+ """XPath extension function converting all entites in passed text."""
+ if isinstance(text, list):
+ text = ''.join(text)
+ for entity, substitutution in ENTITY_SUBSTITUTIONS:
+ text = text.replace(entity, substitutution)
+ return text
+
+
+# Register substitute_entities function with lxml
+ns = etree.FunctionNamespace('http://wolnelektury.pl/functions')
+ns['substitute_entities'] = substitute_entities
+
+