Foo = Class.new Foo.class_eval do def class_bar "class_bar" end end Foo.instance_eval do def instance_bar "instance_bar" end end Foo.class_bar #=> undefined method ‘class_bar’ for Foo:Class Foo.new.class_bar #=> "class_bar" Foo.instance_bar #=> "instance_bar" Foo.new.instance_bar #=> undefined method ‘inst...
Foo = Class.new Foo.instance_eval do def instance_bar "instance_bar" end end puts Foo.instance_bar #=> "instance_bar" puts Foo.new.instance_bar #=> undefined method ‘instance_bar’ My understanding is that calling instance_eval on an object is supposed to allow you to define an instance variable or method for that object...
One thing I'm a bit unclear on is the difference between these NSMutableArray Methods: // Class Method Style NSMutableData *myMutableDataInstance = [NSMutableData dataWithLength:WholeLottaData]; and // Instance Method Style NSMutableData *myMutableDataInstance = nil; myMutableDataInstance = [[[NSMutableData alloc] initWithLength:...
It seems that Python has some limitations regarding instance methods. Instance methods can't be copied. Instance methods can't be pickled. This is problematic for me, because I work on a very object-oriented project in which I reference instance methods, and there's use of both deepcopying and pickling. The pickling thing is done mos...
In Ruby, suppose I have a class Foo to allow me to catalogue my large collection of Foos. It's a fundamental law of nature that all Foos are green and spherical, so I have defined class methods as follows: class Foo def self.colour "green" end def self.is_spherical? true end end This lets me do Foo.colour # "green" ...