self.module_eval?

[Douglas Livingstone]

Why does this work:

class ComplexObject
attr_accessor :colour
def initialize # :yield: c
ComplexObject.module_eval "undef_method :colour="
end
end

But this doesn't?

class ComplexObject
attr_accessor :colour
def initialize # :yield: c
self.module_eval "undef_method :colour="
end
end

(btw, I know about attr_reader, I'm just looking for ways around the
"disadvantages" for "Initializing complex objects" at
http://www.rubygarden.org/ruby?RubyIdioms )

I assumed that self == ComplexObject, but obviously not... why is that?

Cheers,
Douglas

 

[James Edward Gray II]

Why does this work:

class ComplexObject
attr_accessor :colour
def initialize # :yield: c
ComplexObject.module_eval "undef_method :colour="
end
end

But this doesn't?

class ComplexObject
attr_accessor :colour
def initialize # :yield: c
self.module_eval "undef_method :colour="
end
end

(btw, I know about attr_reader, I'm just looking for ways around the
"disadvantages" for "Initializing complex objects" at
http://www.rubygarden.org/ruby?RubyIdioms )

I assumed that self == ComplexObject, but obviously not... why is that?

When initialize() gets called, "self" will be setup to point to the
current object, as is always true with Ruby instance methods. If you
want to fetch the object's class, without hardcoding it, use
"self.class..."

Hope that helps.

James Edward Gray II