module Padrino::Utils

def build_uri_query(object, namespace = nil)


Utils.build_uri_query(:a => { :d => 2 }, :b => 3) #=> ~"a[d]=2&b=3"
Utils.build_uri_query([1, 2], 'namespace') #=> ~"namespace[]=1&namespace[]=2"
Utils.build_uri_query(:a => [1, 2]) #=> ~"a[]=1&a[]=2"
Utils.build_uri_query(:a => 1, :b => 2) #=> "a=1&b=2"

Examples (~ marks here that output is actually escaped by CGI):

Builds an URI query from a Hash or any Object.
# 
def build_uri_query(object, namespace = nil)
  case object
  when Hash
    object.map do |key, value|
      next if value == {} || value == []
      build_uri_query(value, namespace ? "#{namespace}[#{key}]" : key)
    end.compact.join('&')
  when Array
    fail ArgumentError, 'namespace is missing' unless namespace
    (object.empty? ? [''] : object).map do |value|
      build_uri_query(value, "#{namespace}[]")
    end.join('&')
  else
    fail ArgumentError, 'namespace is missing' unless namespace
    "#{CGI.escape(namespace.to_s)}=#{CGI.escape(object.to_s)}"
  end
end

def deep_dup(object)


Recursively duplicates the passed object.
# 
def deep_dup(object)
  case object
  when Array
    object.map{ |value| deep_dup(value) }
  when Hash
    object.each_with_object(object.dup.clear) do |(key, value), new_hash|
      new_hash[deep_dup(key)] = deep_dup(value)
    end
  when NilClass, FalseClass, TrueClass, Symbol, Numeric, Method
    object
  else
    begin
      object.dup
    rescue TypeError
      object
    end
  end
end

def symbolize_keys(hash)


Returns a Hash with keys turned into symbols.
# 
def symbolize_keys(hash)
  result = hash.class.new
  hash.each_key do |key|
    result[(key.to_sym rescue key)] = hash[key]
  end
  result
end