Rails - Mar 2006 - Shared Columns in an STI

I have a an STI table which acts_as_tree, that has a large number of
classes/types. My common fields are:

id
parent_id
name
description

with 4 more text fields, I could cover most of my classes if I could
redefine the name of the field like this.

text1 AS address1
text2 AS address2
text3 AS zipcode

For one class and

text 1 AS model_number
text2 AS vendor


Is there a construct that will allow me to do this?

Thanks
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On Sun, Mar 26, 2006 at 07:48:33AM -0500, Jim Schmidt wrote:
} I have a an STI table which acts_as_tree, that has a large number of
} classes/types. My common fields are:
} 
} id
} parent_id
} name
} description
} 
} with 4 more text fields, I could cover most of my classes if I could
} redefine the name of the field like this.
} 
} text1 AS address1
} text2 AS address2
} text3 AS zipcode
} 
} For one class and
} 
} text 1 AS model_number
} text2 AS vendor
} 
} 
} Is there a construct that will allow me to do this?

I just wrote something to do that for similar reasons:

class Super < ActiveRecord::Base
  
  def self.alias_field(old_field, new_field)
    define_method(new_field) { self.send(old_field) }
    define_method("#{new_field}=") { |arg|
self.send("#{old_field}=", arg) }
    define_method("#{new_field}?") {
self.send("#{old_field}?") }
  end

end

class Sub < Super
  alias_field :text1, :address1
  alias_field :text2, :address2
  alias_field :text3, :zipcode
end

Now I can do all of the following:

fail "Where''s the address?" unless foo.address1?
foo.address1 = ''1600 Pennsylvania Ave.''
addr = foo.address1

...and it will use text1?, text1=, and text1, respectively.

} Thanks
--Greg

Thanks, that is exactly what I need.



On 3/26/06, Gregory Seidman <gsslist+ror@anthropohedron.net>
wrote:
>
> On Sun, Mar 26, 2006 at 07:48:33AM -0500, Jim Schmidt wrote:
> } I have a an STI table which acts_as_tree, that has a large number of
> } classes/types. My common fields are:
> }
> } id
> } parent_id
> } name
> } description
> }
> } with 4 more text fields, I could cover most of my classes if I could
> } redefine the name of the field like this.
> }
> } text1 AS address1
> } text2 AS address2
> } text3 AS zipcode
> }
> } For one class and
> }
> } text 1 AS model_number
> } text2 AS vendor
> }
> }
> } Is there a construct that will allow me to do this?
>
> I just wrote something to do that for similar reasons:
>
> class Super < ActiveRecord::Base
>
>   def self.alias_field(old_field, new_field)
>     define_method(new_field) { self.send(old_field) }
>     define_method("#{new_field}=") { |arg|
self.send("#{old_field}=", arg)
> }
>     define_method("#{new_field}?") {
self.send("#{old_field}?") }
>   end
>
> end
>
> class Sub < Super
>   alias_field :text1, :address1
>   alias_field :text2, :address2
>   alias_field :text3, :zipcode
> end
>
> Now I can do all of the following:
>
> fail "Where''s the address?" unless foo.address1?
> foo.address1 = ''1600 Pennsylvania Ave.''
> addr = foo.address1
>
> ...and it will use text1?, text1=, and text1, respectively.
>
> } Thanks
> --Greg
>
> _______________________________________________
> Rails mailing list
> Rails@lists.rubyonrails.org
> http://lists.rubyonrails.org/mailman/listinfo/rails
>
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