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Nafeez Quraishi
12,416 Pointsin `<main>': undefined method `push' for nil:NilClass (NoMethodError)
Having a hard time to identify what i am not doing right here. My code is almost a copy of what is given in the example:
require "./Contact"
class AddressBook
attr_accessor :contacts
def intitialize
@contacts = []
end
def print_contact_list
contacts.each do |contact|
puts contact.to_s('last_first')
end
end
end
me = Contact.new
me.first_name = "AAA"
me.middle_name = "BBB"
me.last_name = "CCC"
me.add_phone_number('first_no', '111111111')
me.add_phone_number('second_no', '1111122222')
me.add_address('Home', "my house", 'my street one', 'my city', "my state", "999999")
me.add_address('Office', 'my office', 'my office street', 'my city', "my state", '9999111')
my_frnd = Contact.new
my_frnd.first_name = "DDD"
my_frnd.middle_name = "EEE"
my_frnd.last_name = "FFF"
my_frnd.add_address('Home', "frnd house", 'frnd street one', 'frnd city', "frnd state", "999999")
my_frnd.add_address('Office', 'frnd office', 'frnd office street', 'frnd city', "frnd state", '9999111')
address_book = AddressBook.new
address_book.contacts.push(me)
address_book.contacts.push(my_frnd)
address_book.print_contacts_list
2 Answers
Nafeez Quraishi
12,416 PointsMade contacts a global variable i.e. $contacts and that worked.
Jay McGavren
Treehouse TeacherNafeez Quraishi sorry you didn't get an answer on this sooner!
I would not recommend using global variables. They eliminate "encapsulation", meaning that a bug in one part of your program can cause problems that show up in a completely different part of your program, and you will have a very hard time finding the real source of the problem. Instead, we should try to fix the real source of this error.
It looks like the main problem is a simple typo - the name of the initialize method was misspelled, and so @contacts wasn't getting initialized. My updates to your code are below, with comments.
# I changed this to lower-case to match the name of the "contact.rb" file.
require "./contact"
class AddressBook
attr_accessor :contacts
# This here was the main problem.
# You had a typo "intitialize", in the name of this method. So when you
# called AddressBook.new, Ruby looked for a method named "initialize",
# saw that there wasn't one, and did nothing. That's why you were getting
# "undefined method 'push' for nil:NilClass": @contacts was still set to
# nil.
def initialize
@contacts = []
end
def print_contact_list
contacts.each do |contact|
puts contact.to_s('last_first')
end
end
end
me = Contact.new
me.first_name = "AAA"
me.middle_name = "BBB"
me.last_name = "CCC"
me.add_phone_number('first_no', '111111111')
me.add_phone_number('second_no', '1111122222')
me.add_address('Home', "my house", 'my street one', 'my city', "my state", "999999")
me.add_address('Office', 'my office', 'my office street', 'my city', "my state", '9999111')
my_frnd = Contact.new
my_frnd.first_name = "DDD"
my_frnd.middle_name = "EEE"
my_frnd.last_name = "FFF"
my_frnd.add_address('Home', "frnd house", 'frnd street one', 'frnd city', "frnd state", "999999")
my_frnd.add_address('Office', 'frnd office', 'frnd office street', 'frnd city', "frnd state", '9999111')
address_book = AddressBook.new
address_book.contacts.push(me)
address_book.contacts.push(my_frnd)
# Fixed a typo in the method name here.
address_book.print_contact_list