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Re: Making a simple parser

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Felipe Balbi wrote in post #993252:
> Hi all,
>
> To automate some of the tests I have to run, I decided to use ruby to
> generate some script files on a particular (very simple) language based
> on several possible input files. My first approach at this was to use
> inherited method on a parent class (which I called InputFormat) to hold
> all the children in an array. Then, different formats could become a
> child class of InputFormat and return a known data format (I decided to
> use an array of hashes because the output is really really simple) to
> the output generator code.
>
> So the idea is something like:
>
> class InputFormat
>   @children = []
>
>   def initialize(input)
>     @input = input
>   end
>
>   def parse
>     @children.each { |child|
>       child.parse(@input) if child.supported?(@input)
>     }
>   end
>
>   def self.inherited(child)
>     @children << child
>   end
> end
>
> class AInputFormat < InputFormat
>   def supported?
>     # check if we can parse this type of file
>   end
>
>   def parse
>     # parse and generate array of hashes in known format
>   end
> end
>
>
> Then on the core file I would have something like:
>
> input = InputFormat.new(ARGV[0])
> input.parse
>
> As it turns out, this isn't working because AInputFormat will only
> inherit from InputFormat at the time I actually use it, am I right ?
>

No:

1)
class A
  def self.inherited(child)
    puts 'inherited called'
  end
end

class B < A
end

--output:--
inherited called


2)
class A
  def self.inherited(child)
    puts 'inherited called'
  end
end

B = Class.new(A)

--output:--
inherited called

> possible input formats generate one output format)

-- 
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Thread

Making a simple parser Felipe Balbi <balbif@gmail.com> - 2011-04-16 14:52 -0500
  Re: Making a simple parser 7stud -- <bbxx789_05ss@yahoo.com> - 2011-04-16 22:31 -0500
  Re: Making a simple parser jake kaiden <jakekaiden@yahoo.com> - 2011-04-17 12:01 -0500
    Re: Making a simple parser Felipe Balbi <balbif@gmail.com> - 2011-04-17 15:22 -0500
      Re: Making a simple parser jake kaiden <jakekaiden@yahoo.com> - 2011-04-17 21:10 -0500
  Re: Making a simple parser Jesús Gabriel y Galán <jgabrielygalan@gmail.com> - 2011-04-18 02:22 -0500
    Re: Making a simple parser Felipe Balbi <balbif@gmail.com> - 2011-04-19 16:03 -0500
  Re: Making a simple parser 7stud -- <bbxx789_05ss@yahoo.com> - 2011-04-18 13:24 -0500
    Re: Making a simple parser 7stud -- <bbxx789_05ss@yahoo.com> - 2011-04-18 15:22 -0500

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