#
# = ostruct.rb: OpenStruct implementation
#
# Author:: Yukihiro Matsumoto
# Documentation:: Gavin Sinclair
#
# OpenStruct allows the creation of data objects with arbitrary attributes.
# See OpenStruct for an example.
#
#
# OpenStruct allows you to create data objects and set arbitrary attributes.
# For example:
#
# require 'ostruct'
#
# record = OpenStruct.new
# record.name = "John Smith"
# record.age = 70
# record.pension = 300
#
# puts record.name # -> "John Smith"
# puts record.address # -> nil
#
# It is like a hash with a different way to access the data. In fact, it is
# implemented with a hash, and you can initialize it with one.
#
# hash = { "country" => "Australia", :population => 20_000_000 }
# data = OpenStruct.new(hash)
#
# p data # -> <OpenStruct country="Australia" population=20000000>
#
class OpenStruct
#
# Create a new OpenStruct object. The optional +hash+, if given, will
# generate attributes and values. For example.
#
# require 'ostruct'
# hash = { "country" => "Australia", :population => 20_000_000 }
# data = OpenStruct.new(hash)
#
# p data # -> <OpenStruct country="Australia" population=20000000>
#
# By default, the resulting OpenStruct object will have no attributes.
#
def initialize(hash=nil)
@table = {}
if hash
for k,v in hash
@table[k.to_sym] = v
new_ostruct_member(k)
end
end
end
# Duplicate an OpenStruct object members.
def initialize_copy(orig)
super
@table = @table.dup
end
def marshal_dump
@table
end
def marshal_load(x)
@table = x
@table.each_key{|key| new_ostruct_member(key)}
end
def modifiable
if self.frozen?
raise TypeError, "can't modify frozen #{self.class}", caller(2)
end
@table
end
protected :modifiable
def new_ostruct_member(name)
name = name.to_sym
unless self.respond_to?(name)
class << self; self; end.class_eval do
define_method(name) { @table[name] }
define_method("#{name}=") { |x| modifiable[name] = x }
end
end
name
end
def method_missing(mid, *args) # :nodoc:
mname = mid.id2name
len = args.length
if mname.chomp!('=')
if len != 1
raise ArgumentError, "wrong number of arguments (#{len} for 1)", caller(1)
end
modifiable[new_ostruct_member(mname)] = args[0]
elsif len == 0
@table[mid]
else
raise NoMethodError, "undefined method `#{mname}' for #{self}", caller(1)
end
end
#
# Remove the named field from the object.
#
def delete_field(name)
@table.delete name.to_sym
end
InspectKey = :__inspect_key__ # :nodoc:
#
# Returns a string containing a detailed summary of the keys and values.
#
def inspect
str = "#<#{self.class}"
ids = (Thread.current[InspectKey] ||= [])
if ids.include?(object_id)
return str << ' ...>'
end
ids << object_id
begin
first = true
for k,v in @table
str << "," unless first
first = false
str << " #{k}=#{v.inspect}"
end
return str << '>'
ensure
ids.pop
end
end
alias :to_s :inspect
attr_reader :table # :nodoc:
protected :table
#
# Compare this object and +other+ for equality.
#
def ==(other)
return false unless(other.kind_of?(OpenStruct))
return @table == other.table
end
end
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