From: Trans <transfire@...>
Date: 2007-08-24T13:28:57+09:00
Subject: Re: Dynamic methods



On Aug 23, 6:46 pm, -j B- <jrb...@drexel.edu> wrote:
> I have seen examples of catching unkown methods called on a class with
> method_missing.
> For example:
>
> class Example
>    def initialize(...)
>       #...
>    end
>
>    def method_missing(item)
>       call = item.id2name
>       process(call)
>    end

  def method_missing(item, *args, &blk)
    process(item, *args, &blk)   # item is already a symbol
  end

> end
>
> But I'm not sure if that is an 'acceptable' way to do things. Also,
> suppose that I wanted to add a method dynamically that takes arguments,
> is this even possible?
> My general thought is allowing functionality to be added to a program
> dynamically based on a set of rules in a config file.
> Any suggestions are welcome.
> Thank you.

Also, keep in mind Ruby classes are open. You can add real methods to
them on the fly.

  class Example
  end

  foo = "bar"

  Example.class_eval %{
    def #{foo}
      "#{foo}"
    end
  }

  Example.new.foo #=> "bar"

T.