Use block style gsub to avoid interpretation as backref
Use block style gsub to avoid interpretation as backref

replacement style gsub caused strings like "\\+" to be interpreted as
backreference and completely disappear to "", see
<http://www.ruby-doc.org/core/classes/String.html#M001186>.

knuton/hobbes,knuton/hobbes,knuton/hobbes,knuton/hobbes