This entry is for Ruby beginners.
Assume you have class A and want to define a class method c.
class + def + self.
singleton class
class_eval + def
Assume you have class A and want to define an instance method i.
class + def
instance_eval + def
class_eval + define_method
The stable version of MRI 1.9.2 will be released soon. Let's compare the differences between the latest ruby and the legacy ruby.
Here this is the diff of the public methods of Kernel class on ruby 1.9.2dev and 1.8.7. I just used such command: ruby -ve 'puts Kernel.public_methods.sort'.
The differences were more than I thought.
! became a method from a build-in operatorKernel.chomp worked like Perl, targetting $_, but now it was eliminatedclass_variable_get/set is now available besides instance_variable_get/setdefine_singleton_method!spawn!