I am practicing/learning Ruby using Study Notes from www.ruby-lang.org.
I am working on Validation program taken from Ruby Cookbook, but
unable to run program as is. Please advise where I may have gone
wrong.
Thanks in advance. JSU
# p050inputvalidation.rb
# Here's an example from the Ruby Cookbook,
# showing how one can do validation of user's inputs.
class Name
# Define default getter methods, but not setter methods.
attr_reader :first, :last
# When someone tries to set a first name,
# enforce rules about it.
def first=(first)
if (first == nil or first.size == 0)
raise ArgumentError.new('Everyone must have a first name.')
end
first = first.dup
first[0] = first[0].chr.capitalize
@first = first
end
# When someone tries to set a last name,
# enforce rules about it.
def last=(last)
if (last == nil || last.size == 0)
raise ArgumentError.new('Everyone must have a last name.')
end
last[0] = last[0].chr.capitalize
@last = last
end
def full_name
"#{@first} #{@last}"
end
# Delegate to the setter methods instead of
# setting the instance variables directly.
def initialize(first, last)
self.first = first
self.last = last
end
end
jacob = Name.new('Jacob', 'Berendes')
jacob.first = 'Mary Sue'
jacob.full_name # => "Mary Sue Berendes"
john = Name.new('John', 'Von Neumann')
john.full_name # "John Von Neumann"
john.first = 'john'
john.first # => "john"
john.first = nil
# ArgumentError: Everyone must have a first name.
Name.new('Kero, international football star and performance artist',
nil)
# ArgumentError: Everyone must have a last name.
And my output is as follows:
ruby p050inputvalidation.rb
p050inputvalidation.rb:11:in `first=': Everyone must have a first
name. (ArgumentError)
from p050inputvalidation.rb:46
Exit code: 1
Thanks again!