Creating variable inside a class

Ruby
1

All I want to do, is to create a new variable called data_dfp inside the
class, and be able to set/get it’s value from outside

require ‘nokogiri’
class MyDocument < Nokogiri::XML::SAX::Document
attr_accessor :data_dfp

def start_element(name, attrs = [])
puts “#{name}”
end
end

parser = Nokogiri::XML::SAX::Parser.new(MyDocument.new)
parser.data_dfp = 4
puts parser.data_dfp

Error
nokoteste.rb:12:in <main>': undefined methoddata_dfp=’ for
#Nokogiri::XML::SAX::Parser:0x007fcc1413bea0 (NoMethodError)

Whats the right way of doing this?

2

On 06/08/13 08:35, Renato Co wrote:

end

parser = Nokogiri::XML::SAX::Parser.new(MyDocument.new)
^^ I’m not sure what this is supposed to mean.

Have you tried simply:

parser = MyDocument.new

I’m not familiar with nokogiri, is it supposed to take something in its
constructor?

parser.data_dfp = 4
puts parser.data_dfp

Error
nokoteste.rb:12:in <main>': undefined methoddata_dfp=’ for
#Nokogiri::XML::SAX::Parser:0x007fcc1413bea0 (NoMethodError)

Whats the right way of doing this?

Sam

3

Sam D. wrote in post #1117822:

On 06/08/13 08:35, Renato Co wrote:

end

parser = Nokogiri::XML::SAX::Parser.new(MyDocument.new)
^^ I’m not sure what this is supposed to mean.

I with I knew it too…

Several attempts later turns out this works(for now)

parser = Nokogiri::XML::SAX::Parser.new(MyDocument.new(4))

I am very novice at ruby in general…

ty for helping

forget to say I added a method

def initialize(data=[])
@data_dfp = data
end

4

On 06/08/13 10:19, Renato Co wrote:

parser = Nokogiri::XML::SAX::Parser.new(MyDocument.new(4))

I am very novice at ruby in general…

ty for helping

Cool, go forth and conquer =]

5

On Mon, Aug 5, 2013 at 5:35 PM, Renato Co [email protected] wrote:

end

parser = Nokogiri::XML::SAX::Parser.new(MyDocument.new)
parser.data_dfp = 4
puts parser.data_dfp

data_fp is defined at the MyDocument and not at the parser.

parser.document # Returns the “MyDocument” instance you want.

So you should…

parser.document.data_dfp = 4
puts parser.document.data_dfp

Was this what you were trying to accomplish?

6

On Aug 5, 2013, at 3:35 PM, Renato Co [email protected] wrote:

All I want to do, is to create a new variable called data_dfp inside the
class, and be able to set/get it’s value from outside

require ‘nokogiri’
class MyDocument < Nokogiri::XML::SAX::Document

When you did this, you created a new class that inherits from
Nokogiri::XML::SAX::Document

attr_accessor :data_dfp

def start_element(name, attrs = [])
puts “#{name}”
end
end

parser = Nokogiri::XML::SAX::Parser.new(MyDocument.new)

But then you assigned parser to a new Nokogiri::XML::SAX::Parser object.
The MyDocument.new will get eaten up by the enclosing .new. Since you
defined the instance variable and setters/getters in the inherited
class, they will not be in the Nokogiri::XML::SAX::Parser class, and
thus not in the instance.

If instead you make parser an instance of MyDocument, you’d get them:

parser = MyDocument.new