include module in module

[Ittay Dror]

Hi,


I have a situation like this:

module M

....

end


class C1

include M

...

end


class C2

include M

...

end


Now I want to add methods to C1 and C2 and whatever other class includes M.


My first approach was:

module S

....

end


module M

include S

end


But this doesn't work (meaning whatever methods I have in S are
undefined for instances of C1, C2).


So, how can I do that?


Thanks,

Ittay

 

[Ittay Dror]

Hi,


I have a situation like this:

module M

....

end


class C1

include M

...

end


class C2

include M

...

end


Now I want to add methods to C1 and C2 and whatever other class
includes M.


My first approach was:

module S

....

end


module M

include S

end


But this doesn't work (meaning whatever methods I have in S are
undefined for instances of C1, C2).


So, how can I do that?

I think I solved it:
module S
def self.included(other)
methods = instance_methods(false)
other.module_eval do
methods.each do |name|
name = name.to_sym
base.send :define_method, name, instance_method(name)
end
end
end
end

Ittay

 

[Robert Klemme]

I have a situation like this:

module M
end

class C1
include M
end

class C2
include M
end

Now I want to add methods to C1 and C2 and whatever other class includes M.

So, how can I do that?

There are at least these two possible approaches

1. add methods to M
2. create another module S and include it in all classes inheriting M
2b. same as 2 but insert S only in the inheritance hierarchy of
classes that directly include M

#!/bin/env ruby

module M
def m
"Mmmmh!"
end
end

class A
include M
end

class B
include M
end

# approach 1

module M
def late
"late"
end
end

puts A.new.late, B.new.late

# approach 2

module S
def even_later
"even_later"
end
end

ObjectSpace.each_object(Class) do |cl|
if cl.ancestors.include?(M) && !cl.ancestors.include?(S)
cl.class_eval { include S }
end
end

puts A.new.even_later, B.new.even_later

# approach 2b

module S2
def x
"X"
end
end

ObjectSpace.each_object(Class) do |cl|
a = cl.ancestors
i = a.index(M)
if i && a[1...i].all? {|c| not Class === c}
cl.class_eval { include S2 }
end
end

puts A.new.x, B.new.x

Cheers

robert