Rack rack

The current state of affairs with regard to parsing params.

For: "foo=bar&foo=baz"

{"foo" => "bar"} # rails
{"foo" => "baz"} # merb
{"foo" => ["bar", "baz"]}

Proposal: Use a MultiHash Object

This idea is cribbed from the WebOb Python framework, which provides some core objects for the WSGI spec.

Semantics

params["foo"]     #=> "baz"
params.all("foo") #=> ["bar", "baz"]
params.each do |key, value|
  p [key, value]
end
                  #=> ["foo", "baz"]

The initial implementation also handles update, update!, merge, merge!, delete, and supplies each_array, which yields [key, values] to the block.

The initial motivation for this was correctly handling checkboxes that supply both a "yes" and "no" value when checked (["1","0"] in Rails and ["0","1"] in Merb) and a "no" value when not checked ("0").