def camelize(str)
      call_or_yield str do
        str.to_s.sub(/^[a-z\d]*/) { $&.capitalize }.gsub(/(?:_|(\/))([a-z\d]*)/) { "#{$1}#{$2.capitalize}" }.gsub('/', '::')
      end
    end
def camelize(str)
      call_or_yield str do
        str.to_s.sub(/^[a-z\d]*/) { $&.capitalize }.gsub(/(?:_|(\/))([a-z\d]*)/) { "#{$1}#{$2.capitalize}" }.gsub('/', '::')
      end
    end
Converts strings to UpperCamelCase.
 @param [String] str
 @return [String]