Ruby struct reset method - ruby

Question

I have a large struct, and after creating an object and setting some of the members to values, I want to be able to set all the members of the object to nil. I tried the following, which doesn't work for some reason:
My_struct = Struct.new(
:member1,
:member2,
:member3
) do
def reset
self.each {|x| x = nil }
end
end
myblock = My_struct.new
puts myblock.member1
myblock.member1 = "value"
puts myblock.member1
myblock.reset
puts myblock.member1
I expected that last puts to return "" but it returns "value". What have I done wrong? Is there a native method, other than destroying and recreating the object each time?

Answer 1

self.each is iterating over the values, not the members/keys of the struct. This should do what you want.
My_struct = Struct.new(
:member1,
:member2,
:member3
) do
def reset
self.members.each {|k| send("#{k}=", nil)}
end
end
myblock = My_struct.new
myblock.member1
#=> nil
myblock.member1 = "value"
#=> "value"
myblock.member1
#=> "value"
myblock.reset
myblock.member1
#=> nil

Answer 2

Problem
I have a large struct, and after creating an object and setting some of the members to values, I want to be able to set all the members of the object to nil.
Solution: Just Replace the Whole Struct Object
Unless you have a special need to keep the object ID the same, the easiest thing to do is simply to create a new Struct, because the documentation for Struct#new says:
Unset parameters default to nil.
For example:
My_struct = Struct.new :member1, :member2, :member3
m = My_struct.new 'foo', 'bar', 'baz'
#=> #<struct My_struct member1="foo", member2="bar", member3="baz">
m = My_struct.new
#=> #<struct My_struct member1=nil, member2=nil, member3=nil>
Obviously, m.object_id will differ every time you assign a new My_struct instance to m, but there are very few use cases where this would (or should) matter. It's certainly a lot easier and less prone to errors than trying to reassign individual members, but your mileage may vary.

Answer 3

My_struct = Struct.new(:member1, :member2, :member3) do
def reset
initialize
end
end
myblock = My_struct.new
myblock.member1 = "value"
p myblock.object_id # => 15379000
myblock.reset
p myblock.member1 # => nil
p myblock.object_id # => 15379000; same object

Answer 4

My_struct = Struct.new(
:member1,
:member2,
:member3
) do
def reset
members.each { |m| self[m] = nil }
end
end
m = My_struct.new #=> #<struct My_struct member1=nil, member2=nil, member3=nil>
m.member1 = "Billy-Bob"
m.member2 = "Girtie"
m.member3 = "Hector"
m.member1 #=> "Billy-Bob"
m.member2 #=> "Girtie"
m.member3 #=> "Hector"
m.reset
m.member1 #=> nil
m.member2 #=> nil
m.member3 #=> nil

Answer 5

I've tried with ruby 2.2.4. All fields a nil by default?
But I've found a way you could change fields you like
require 'pp'
MyStruct = Struct.new( :member, :user, :parent ) do
def initialize
self.members.each { | elem | self.send( "#{elem}=", 1 ) }
end
end
pp MyStruct.new
UPDATE: I had to changed the code. Comment below was right. Now it's working