module CGI::HtmlExtension

#
radio_button("NAME" => "name", "VALUE" => "value", "ID" => "foo")

#
radio_button("name", "value", true)

#
radio_button("name", "value")

Alternatively, the attributes can be specified as a hash.

starts off checked.
the field if checked. +checked+ specifies whether the field
+name+ is the name of the input field. +value+ is the value of

Generates a radio-button Input element.

def radio_button(name = "", value = nil, checked = nil)
  attributes = if name.kind_of?(String)
                 { "TYPE" => "radio", "NAME" => name,
                   "VALUE" => value, "CHECKED" => checked }
               else
                 name["TYPE"] = "radio"
                 name
               end
  input(attributes)
end