Question about how ruby sources is parsed

Ruby
1

Hi,

I recently came came up with this piece of (monkey-inspired) code:

class String0 < String
    def foo
        123
    end
end

Object.send :remove_const, :String
String = String0

This makes the following two statements work as intended:

p String0.new("foo").foo # => 123
p String.new("foo").foo # => 123

The following doesn’t work though:

p "foo".foo
p eval %{"foo".foo}

undefined method `foo' for "foo":String (NoMethodError)

Has somebody an idea if it is possible to make the ruby parser use
the
new String class somehow? I assume there is no way to make this work
but
then: I’d be happy if somebody proves me wrong.

Regards,
Thomas.

2

That’s weird looking stuff, I can’t imaging that it’s good to do thing
that way.

What’s wrong with

class String
def foo
123
end
end

?

Jason

3

What’s wrong with

class String
def foo
123
end
end

Nothing if that’s what you want.

The above question was inspired by certain posts to the monkey-thread
and the idea of stacked classes/methods, the proposal of module-
specific hacks and the idea of Module.import/rename (I looked at the
original library referenced by Pit Captain but didn’t find the
extended one). Whether it’s useful … Currently I’m rather interested
in if it’s possible.

Regards,
Thomas.

4

On Feb 27, 2008, at 07:19 AM, ThoML wrote:

undefined method `foo’ for “foo”:String (NoMethodError)

Has somebody an idea if it is possible to make the ruby parser use
the new String class somehow? I assume there is no way to make this
work
but then: I’d be happy if somebody proves me wrong.

You can’t do this without modifying the interpreter.

5

I think “” is hard-wired to constructing String class objects, as the {}
is to creating Hash and [] is to creating Array.

Best regards,

Jari W.