ext(newext='')
Replace the file extension with newext. If there is no extension on the string, append the new extension to the end. If the new extension is not given, or is the empty string, remove any existing extension.
ext is a user added method for the String class.
This String extension comes from Rake
# File lib/rake/ext/string.rb, line 13 def ext(newext='') return self.dup if ['.', '..'].include? self newext = (newext =~ /^\./) ? newext : ("." + newext) if newext != '' self.chomp(File.extname(self)) << newext end